I am having trouble achieving an expected output. I am trying to create a byte adder using logical operators such as AND, XOR and OR. I have taken the minimal code required to reproduce the problem out of code, so assume that finalfirstvalue = "1010" and finalsecondvalue = "0101".
secondvalueindex = (len(finalsecondvalue) - 1)
carry, finalans = False, []
for i in range(-1, -len(finalfirstvalue) - 1, -1):
andone = (bool(finalfirstvalue[i])) & (bool(finalsecondvalue[secondvalueindex]))
xorone = (bool(finalfirstvalue[i])) ^ (bool(finalsecondvalue[secondvalueindex]))
andtwo = (bool(carry)) & (bool(xorone))
xortwo = (bool(carry)) ^ (bool(xorone))
orone = (bool(andone)) | (bool(andtwo))
carry = (bool(orone))
finalans.append(xortwo)
secondvalueindex -= 1
answer = ''.join(str(e) for e in finalans)
print (answer)
Actual Output: FalseTrueTrueTrue
Expected Output: TrueTrueTrueTrue
The code then follows to change back into zeroes and ones.
Because its missing a single boolean I feel like the issue is with my indexing. Although I've played around with it a bit and not had any luck.
I need to carry out these operations on the two variables mentioned at the start, but for the right most elements, and then move to the left by one for the next loop and so on.
First mistake is You are representing your binary numbers as string values.
finalfirstvalue = "1010"
finalsecondvalue = "0101"
secondvalueindex = (len(finalsecondvalue) - 1) == 3
So in second for loop you will get the result as
(finalsecondvalue[secondvalueindex]) == '0'
If you check in your Idle
>>> bool('0')
True
>>>
Because '0' is not actual 0 it is an non-empty string so it return True.
You need to cast your result to int before checking them with bool
Like this
(bool(int(finalsecondvalue[secondvalueindex])))
EDIT 2 Adding with variable lenghts
Full adder with verification using bin() function
a="011101"
b="011110"
if a>b:
b=b.zfill(len(a))
if a<b:
a=a.zfill(len(b))
finalfirstvalue = a
finalsecondvalue = b
carry, finalans = 0, []
secondvalueindex = (len(finalsecondvalue))
for i in reversed(range(0, len(finalfirstvalue))):
xorone = (bool(int(finalfirstvalue[i]))) ^ (bool(int(finalsecondvalue[i])))
andone = (bool(int(finalfirstvalue[i]))) & (bool(int(finalsecondvalue[i])))
xortwo = (carry) ^ (xorone)
andtwo = (carry) & (xorone)
orone = (andone) | (andtwo)
carry = (orone)
finalans.append(xortwo)
finalans.reverse()
answer=(''.join(str(e) for e in finalans))
print(str(carry)+answer)
print(bin(int(a,2) + int(b,2))) #verification
So I found the issue was to do with carry. I changed my code to look like the following. Prior to this code below, is code to convert binary values to boolean. For instance, all ones will equal True and all zeroes will equal False.
carry, finalans = False, []
indexvalue = (len(finalfirstvalue)-1)
while indexvalue >= 0:
andone = (firstvaluelist[indexvalue]) & (secondvaluelist[indexvalue])
xorone = (firstvaluelist[indexvalue]) ^ (secondvaluelist[indexvalue])
andtwo = (carry) & (xorone)
xortwo = (carry) ^ (xorone)
orone = (andone) | (andtwo)
carry = (orone)
if (carry == True) & (indexvalue == 0):
finalans.append(xortwo)
finalans.append(True)
else:
finalans.append(xortwo)
indexvalue -= 1
for n, i in enumerate(finalans):
if i == False:
finalans[n] = "0"
if i == True:
finalans[n] = "1"
finalans.reverse()
answer = ''.join(str(e) for e in finalans)
print (answer)
So if there was a single value missing, it was still stored in carry from the final loop but did not get the opportunity to be appended to the final result. To fix this, I added in an if statement to check if carry is containing anything (True) and if the loop is on its final loop by checking if indexvalue is at 0. This way, if the inputs are 32 and 32, rather than getting [False, False, False, False, False, False] as the output, the newly entered if statement will add the missing value in.
Related
This is the code I am working with :
newResults = True
pages = 9
while newResults:
Request = f"{url}?key={API_Key}&ts={ts}&hash={hash}&project_id={project_id}&per_page= {per_page}&page={pages}&date_from={date_from}&date_to={date_to}"
r = requests.get(Request)
data = r.json()
for id in data['tickets']:
newResults = id.get('id', False)
pages += 1
Once the code gets to the newResults = id.get('id', False) and the key doesn't exist, it breaks. Tried using an empty list, tried using a string. Tried printing newResult to see what's going on.It doesn't print the optional value.
The loop goes on forever.
What am I getting wrong?
Still no idea why .get() doesn't return False, but here is a way to do it.
newResults = True
pages = 9
while newResults :
ticketsRequest = f"{url}?key={API_Key}&ts={ts}&hash={hash}&project_id={project_id}&per_page={per_page}&page={pages}&date_from={date_from}&date_to={date_to}"
r = requests.get(ticketsRequest)
data = r.json()
total = data['total']
for id in data['tickets']:
#stuff to do
result += 1
pages += 1
if result == total:
print (project_id, total, result)
break
I would like to get the mean of my reaction time column when my stimnum column is equal to 1
I am not sure if i can do this with one simple line of code or if i need to do a for loop.
stimnum = randi([1 3], [1 100]);
y = 1 + 1.*randn(1, 100);
rt = (y.^2) +.01;
A = rand(1,100);
correct = A>=0.2;
Data= [stimnum; rt; correct ]';
Data = dataset({ Data, 'Stimnum', 'RT', 'Correct'});
rtmean = mean (Data.RT{Data.Stimnum == 1});
I've been trying to take a module in Lua and use it to imitate an object. i.e. I made a deck of cards:
local Card = require("Card")
local function firstCard()
Card.newDeck()
Card.drawCard()
return Card.getCard()
end
local function secondCard()
Card.newDeck()
Card.drawCard()
return Card.getCard()
end
first = firstCard()
second = secondCard()
print(first)
print(second)
I set first = firstCard() and second = secondCard() but when I print the two variables second occasionally results as nil. I'm honestly lost. Here's the actual module itself.
local Card = {}
local deck
local value
local number, suit
local index = 0
local getCard
local getValue
function Card.newDeck()
deck = {}
value = {}
for x = 1, 13 do
if x == 1 then
number = "Ace"
elseif x == 11 then
number = "Jack"
elseif x == 12 then
number = "Queen"
elseif x == 13 then
number = "King"
else
number = x
end
for x1 = 1, 4 do
if x1 == 1 then
suit = "Clubs"
elseif x1 == 2 then
suit = "Diamonds"
elseif x1 == 3 then
suit = "Hearts"
else
suit = "Spades"
end
index = index + 1
deck[index] = number.." of "..suit
value[index] = x
end
end
end
function Card.drawCard()
index = math.random(52)
getCard = deck[index]
getValue = value[index]
end
function Card.getCard()
return getCard
end
function Card.getValue()
return getValue
end
function Card.getIndex()
return index
end
return Card
I have limited knowledge of Lua when it comes to Object-Oriented programming and to be honest, I typically only use it for calculations or small games to keep me occupied I'm class- I'm only 16. I'm more used to Java, even though I started using Lua well before I picked up Java. I just want to know if and how I can make this work. For the most part it works, just those occasional nil values.
The problem is that you have declared the index variable local at the top level of your module. That means that the random value of index that you have calculated in your first drawCard() is reused in your second call to newDeck(). You can add print(index) at the start of newDeck() to see what I mean.
There are several ways to solve the problem. One would be to add index = 0 at the top of newDeck(). A better one would be to declare your variables with smaller scoping, i.e. make index local to each function that uses it.
Try to use this instead, seems to work fine, it should print "ERROR NO VALUE" if there is some issue with the index, if that occurs (it shouldn't though), just print the index (in the generateCard() function).
This is the test
local Card = require("Card");
local function firstCard()
Card.newDeck()
return Card.generateCard(); -- two parameters, deck and value
end
local function secondCard()
Card.newDeck()
return Card.generateCard();
end
first = firstCard()
second = secondCard()
print(first)
print(second)
This is the module
local Card = {deck={};value={};};
function Card.newDeck()
local self = Card
local deck = self.deck;
local value = self.value;
local cards = {[1]="Ace",[11]="Jack",[12]="Queen",[13]="King"};
local types = {[1]="Clubs",[2]="Diamonds",[3]="Hearts",[4]="Spades"};
for x = 1, 13 do
for i = 1, 4 do
local _card,_type=(cards[x] or x),types[i];
deck[#deck+1] = _card.." of ".._type
value[#deck+1] = x
end
end
end
function Card.generateCard()
local self = Card;
if(not math.round) then
math.round = function(value) local mi,ma=math.floor(value),math.ceil(value)return(mi+0.5>value and mi or ma)end;
end
local index = math.round(math.random(1000, 52000)/1000);
return (self.deck[index] or "NO VALUE FOR CARD"),(self.value[index] or "NO DECK FOR CARD");
end
return Card
I'm trying to write pseudo-code and an algorithm in Matlab, to return all the subsequences of a string.
So the string X = {ABCD} will return XSubSequence = {A, B, C, D, AB, AC, AD, BC, BD, CD, ABC, ABD, BCD, ABCD}, order does not matter of course.
clear
x = 'ABC';
XSize = length(x);
count = 1;
i=1;
for i=1:XSize
ZSubSequence{count} = x(i);
count = count + 1;
for j=i+1:XSize
temp = strcat(x(i),x(j));
ZSubSequence{count} = temp;
count = count + 1;
for k=i+2:XSize
if j ~= k
temp = strcat(x(i), x(j), x(k));
ZSubSequence{count} = temp;
count = count + 1;
end
end
end
end
Is there any way to make this more dynamic, so I can add X of any size and it will be able to deal with it?
You might want to consider a completely different approach.
This this is a binary representation of decimal numbers from 1 to 2^length(x)-1. Meaning for your example 1100=12 will be AB and 0011=3 will be CD, 1000 will be A and 1111=2^4-1=15 will be ABCD and so on.
You might want to create this sequence and then translate it into the input output you have.
Example code:
x = 'ABCD';
XSize = length(x);
seq=dec2bin([1:2^XSize-1]);
And now all have left is translate it back to letters
for i=1:1:2^XSize-1
for j=1:1:XSize
if seq(i,j)=='1'
seq(i,j)=x(j);
else
seq(i,j)='_';
end
end
end
Obviously the '_' should be removed and the output formatted the way you want them to be.
This should do it. It only has one loop (no nesting), so it shoud be pretty fast.
x = 'ABCD';
n = length(x);
subseq = x.';
for ii = 2:n
subseq = strvcat(subseq, x(nchoosek(1:n,ii)));
end
subseq_deblanked = deblank(mat2cell(subseq, ones(size(subseq,1),1), n));
The results are:
subseq: char matrix where each row contains a subsequence padded with blank spaces.
subseq_deblanked: cell array of strings with the blank spaces removed, as you specified
This is a question from one of the online coding challenge (which has completed).
I just need some logic for this as to how to approach.
Problem Statement:
We have two strings A and B with the same super set of characters. We need to change these strings to obtain two equal strings. In each move we can perform one of the following operations:
1. swap two consecutive characters of a string
2. swap the first and the last characters of a string
A move can be performed on either string.
What is the minimum number of moves that we need in order to obtain two equal strings?
Input Format and Constraints:
The first and the second line of the input contains two strings A and B. It is guaranteed that the superset their characters are equal.
1 <= length(A) = length(B) <= 2000
All the input characters are between 'a' and 'z'
Output Format:
Print the minimum number of moves to the only line of the output
Sample input:
aab
baa
Sample output:
1
Explanation:
Swap the first and last character of the string aab to convert it to baa. The two strings are now equal.
EDIT : Here is my first try, but I'm getting wrong output. Can someone guide me what is wrong in my approach.
int minStringMoves(char* a, char* b) {
int length, pos, i, j, moves=0;
char *ptr;
length = strlen(a);
for(i=0;i<length;i++) {
// Find the first occurrence of b[i] in a
ptr = strchr(a,b[i]);
pos = ptr - a;
// If its the last element, swap with the first
if(i==0 && pos == length-1) {
swap(&a[0], &a[length-1]);
moves++;
}
// Else swap from current index till pos
else {
for(j=pos;j>i;j--) {
swap(&a[j],&a[j-1]);
moves++;
}
}
// If equal, break
if(strcmp(a,b) == 0)
break;
}
return moves;
}
Take a look at this example:
aaaaaaaaab
abaaaaaaaa
Your solution: 8
aaaaaaaaab -> aaaaaaaaba -> aaaaaaabaa -> aaaaaabaaa -> aaaaabaaaa ->
aaaabaaaaa -> aaabaaaaaa -> aabaaaaaaa -> abaaaaaaaa
Proper solution: 2
aaaaaaaaab -> baaaaaaaaa -> abaaaaaaaa
You should check if swapping in the other direction would give you better result.
But sometimes you will also ruin the previous part of the string. eg:
caaaaaaaab
cbaaaaaaaa
caaaaaaaab -> baaaaaaaac -> abaaaaaaac
You need another swap here to put back the 'c' to the first place.
The proper algorithm is probably even more complex, but you can see now what's wrong in your solution.
The A* algorithm might work for this problem.
The initial node will be the original string.
The goal node will be the target string.
Each child of a node will be all possible transformations of that string.
The current cost g(x) is simply the number of transformations thus far.
The heuristic h(x) is half the number of characters in the wrong position.
Since h(x) is admissible (because a single transformation can't put more than 2 characters in their correct positions), the path to the target string will give the least number of transformations possible.
However, an elementary implementation will likely be too slow. Calculating all possible transformations of a string would be rather expensive.
Note that there's a lot of similarity between a node's siblings (its parent's children) and its children. So you may be able to just calculate all transformations of the original string and, from there, simply copy and recalculate data involving changed characters.
You can use dynamic programming. Go over all swap possibilities while storing all the intermediate results along with the minimal number of steps that took you to get there. Actually, you are going to calculate the minimum number of steps for every possible target string that can be obtained by applying given rules for a number times. Once you calculate it all, you can print the minimum number of steps, which is needed to take you to the target string. Here's the sample code in JavaScript, and its usage for "aab" and "baa" examples:
function swap(str, i, j) {
var s = str.split("");
s[i] = str[j];
s[j] = str[i];
return s.join("");
}
function calcMinimumSteps(current, stepsCount)
{
if (typeof(memory[current]) !== "undefined") {
if (memory[current] > stepsCount) {
memory[current] = stepsCount;
} else if (memory[current] < stepsCount) {
stepsCount = memory[current];
}
} else {
memory[current] = stepsCount;
calcMinimumSteps(swap(current, 0, current.length-1), stepsCount+1);
for (var i = 0; i < current.length - 1; ++i) {
calcMinimumSteps(swap(current, i, i + 1), stepsCount+1);
}
}
}
var memory = {};
calcMinimumSteps("aab", 0);
alert("Minimum steps count: " + memory["baa"]);
Here is the ruby logic for this problem, copy this code in to rb file and execute.
str1 = "education" #Sample first string
str2 = "cnatdeiou" #Sample second string
moves_count = 0
no_swap = 0
count = str1.length - 1
def ends_swap(str1,str2)
str2 = swap_strings(str2,str2.length-1,0)
return str2
end
def swap_strings(str2,cp,np)
current_string = str2[cp]
new_string = str2[np]
str2[cp] = new_string
str2[np] = current_string
return str2
end
def consecutive_swap(str,current_position, target_position)
counter=0
diff = current_position > target_position ? -1 : 1
while current_position!=target_position
new_position = current_position + diff
str = swap_strings(str,current_position,new_position)
# p "-------"
# p "CP: #{current_position} NP: #{new_position} TP: #{target_position} String: #{str}"
current_position+=diff
counter+=1
end
return counter,str
end
while(str1 != str2 && count!=0)
counter = 1
if str1[-1]==str2[0]
# p "cross match"
str2 = ends_swap(str1,str2)
else
# p "No match for #{str2}-- Count: #{count}, TC: #{str1[count]}, CP: #{str2.index(str1[count])}"
str = str2[0..count]
cp = str.rindex(str1[count])
tp = count
counter, str2 = consecutive_swap(str2,cp,tp)
count-=1
end
moves_count+=counter
# p "Step: #{moves_count}"
# p str2
end
p "Total moves: #{moves_count}"
Please feel free to suggest any improvements in this code.
Try this code. Hope this will help you.
public class TwoStringIdentical {
static int lcs(String str1, String str2, int m, int n) {
int L[][] = new int[m + 1][n + 1];
int i, j;
for (i = 0; i <= m; i++) {
for (j = 0; j <= n; j++) {
if (i == 0 || j == 0)
L[i][j] = 0;
else if (str1.charAt(i - 1) == str2.charAt(j - 1))
L[i][j] = L[i - 1][j - 1] + 1;
else
L[i][j] = Math.max(L[i - 1][j], L[i][j - 1]);
}
}
return L[m][n];
}
static void printMinTransformation(String str1, String str2) {
int m = str1.length();
int n = str2.length();
int len = lcs(str1, str2, m, n);
System.out.println((m - len)+(n - len));
}
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
String str1 = scan.nextLine();
String str2 = scan.nextLine();
printMinTransformation("asdfg", "sdfg");
}
}