I have created a Fibonacci program that runs correctly. However I can not figure out how to format the output window the way the problem would like. The rows and spacing are correct but the program should display 6 columns, as it is now the program outputs nine with the ninth cut off. Am I doing something wrong or missing something? I am using the Visual Studio C++ compiler.
#include <iostream>
#include <iomanip>
using namespace std;
void main ()
{
int FirstNum = 1;
int SecondNum = 0;
int Count = 1;
int Answer;
do
{
Answer = FirstNum + SecondNum;
FirstNum = SecondNum;
SecondNum = Answer;
cout << FirstNum << setw (10);
Count++;
} while (Count < 40);
}
This code will generated only 6 columns.
#include <iostream>
#include <iomanip>
using namespace std;
int main ()
{
int FirstNum = 1;
int SecondNum = 0;
int Count = 1;
int Answer;
do
{
Answer = FirstNum + SecondNum;
FirstNum = SecondNum;
SecondNum = Answer;
cout << setw (10)<< FirstNum ;
Count++;
if(Count%6==0)
cout<<endl;
} while (Count < 40);
return 0;
}
Related
I have a c code to show a lowercase of one argument:
This code runs ok when called from commandline with more than 6 argument
however,if called without argument, the demo part does not work ,and programme got stuck:
Below is the code file:
Can anyone help me, Thanks!
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <ctype.h>
int showLowerCase(char *argv[]){
char* aStr = argv[6];
//To lowercase: the demo got stuck probably here
for (int i = 0; aStr[i]; i++) {
aStr[i] = tolower(aStr[i]);
}
printf("a lower case for 6th input string: %s\n",aStr);
}
int main(int argc, char *argv[])
{
if(argc < 7){
// when no srguments given, try a demo:
// change argc to 7
argc = 7;
// make a example of argv2 with 7 strings
char *argv2[7];
argv2[0] = "killWindowsVersatile.exe";
argv2[1] = "key";
argv2[2] = "ci";
argv2[3] = "once";
argv2[4] = "2";
argv2[5] = "1000";
argv2[6] = "SuperCol"; //this argument will be shown as lowercase
showLowerCase(argv2);
return 0;
}
showLowerCase(argv);
return 0;
}
It seems that argv can be modified to lowercase in site, while the argv2 I constructed cannot be modified.
Solved by strcpy:
int showLowerCase(char *argv[]){
printf("aStr = argv[6]\n");
char* aStr = argv[6];
printf("aStr = argv[6]...done");
//make hard copy
char newStr[strlen(aStr)+1];
strcpy(newStr,aStr);
//To lowercase
for (int i = 0; newStr[i]; i++) {
printf("i=0\n");
printf("%c\n",newStr[i]);
newStr[i] = tolower(aStr[i]);
}
printf("a lower case for 6th input string: %s\n",newStr);
}
Threaded quick sort method:
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include "MD5.h"
#include <thread>
using namespace std;
template<typename T>
void quickSort(vector<T> &arr, int left, int right) {
int i = left, j = right; //Make local copys to modify
T tmp; //Termorary variable to use for swaping.
T pivot = arr[(left + right) / 2]; //Find the centerpoint. if 0.5 truncate.
while (i <= j) {
while (arr[i] < pivot) //is i < pivot?
i++;
while (arr[j] > pivot) //Is j > pivot?
j--;
if (i <= j) { //Swap
tmp = arr[i];
arr[i] = arr[j];
arr[j] = tmp;
i++;
j--;
}
};
thread left_t; //Left thread
thread right_t; //Right thread
if (left < j)
left_t = thread(quickSort<T>, ref(arr), left, j);
if (i < right)
right_t = thread(quickSort<T>, ref(arr), i, right);
if (left < j)
left_t.join();
if (left < j)
right_t.join();
}
int main()
{
vector<int> table;
for (int i = 0; i < 100; i++)
{
table.push_back(rand() % 100);
}
cout << "Before" << endl;
for each(int val in table)
{
cout << val << endl;
}
quickSort(table, 0, 99);
cout << "After" << endl;
for each(int val in table)
{
cout << val << endl;
}
char temp = cin.get();
return 0;
}
Above program lags like mad hell and Spams "abort()" has been called.
Im thinking it has something to do with vectors and it Having threading issues
Iv seen the Question asked by Daniel Makardich, His Utilizes a Vector int While mine uses Vector T
You don't have any problem with quick sort, but with passing a templated function to a thread. There is no function quickSort. You need to explicitly give type, to instantiate the function template:
#include <thread>
#include <iostream>
template<typename T>
void f(T a) { std::cout << a << '\n'; }
int main () {
std::thread t;
int a;
std::string b("b");
t = std::thread(f, a); // Won't work
t = std::thread(f<int>, a);
t.join();
t = std::thread(f<decltype(b)>, b); // a bit fancier, more dynamic way
t.join();
return 0;
}
I suspect in your case this should do:
left_t = thread(quickSort<T>, ref(arr), left, j);
And similar for right_t. Also, you have mistake there trying to use operator()() instead of constructing an object. That is why the error is different.
Can't verify though, cause there's no minimal verifiable example =/
I don't know if it's possible to make compiler to use automatic type deduction for f passed as a param, if anyone knows that would probably make it a better answer.
Problem was with thread joins and what #luk32 said
Needed to convert the threads to pointers to threads.
thread* left_t = nullptr; //Left thread
thread* right_t = nullptr; //Right thread
if (left < j)
left_t = new thread(quickSort<T>, ref(arr), left, j);
if (i < right)
right_t = new thread(quickSort<T>, ref(arr), i, right);
if (left_t)
{
left_t->join();
delete left_t;
}
if (right_t)
{
right_t->join();
delete right_t;
}
Seems like if you create a default constructed thread object. But don't use it, it still wants to be joined. and if you do join it, it will complain.
I have looked extensively for the problem in this code, but I can't seem to figure out what tragic error I made and why it is triggering a breakpoint.
(After 3 or 4 inputs, it triggers and I don't know why it doesn't trigger at the start or what is causing it)
#include <conio.h> // For function getch()
#include <cstdlib> // For several general-purpose functions
#include <fstream> // For file handling
#include <iomanip> // For formatted output
#include <iostream> // For cin, cout, and system
#include <string> // For string data type
using namespace std; // So "std::cout" may be abbreviated to "cout", for example.
string convertDecToBin(int dec)
{
int *arrayHex, arraySize = 0;
arrayHex = new int[];
string s = " ";
int r = dec;
for (int i = 0; r != 0; i++)
{
arrayHex[i] = r % 2;
r = r / 2;
arraySize++;
}
for (int j = 0; j < arraySize; j++)
{
s = s + to_string(arrayHex[arraySize - 1 - j]);
}
delete[] arrayHex;
return s;
}
string convertDecToOct(int dec)
{
int *arrayHex, arraySize = 0;
arrayHex = new int[];
string s = " ";
int r = dec;
for (int i = 0; r != 0; i++)
{
arrayHex[i] = r % 8;
r = r / 8;
arraySize++;
}
for (int j = 0; j < arraySize; j++)
{
s = s + to_string(arrayHex[arraySize - 1 - j]);
}
delete[] arrayHex;
return s;
}
int main()
{
int input = 0;
while (input != -1)
{
cout << "\nEnter a decimal number (-1 to exit loop): ";
cin >> input;
if (input != -1)
{
cout << "Your decimal number in binary expansion: " << convertDecToBin(input);
cout << "\nYour decimal number in octal ecpression: " << convertDecToOct(input);
}
}
cout << "\n\nPress any key to exit. . .";
_getch();
return 0;
}
arrayHex = new int[] is your problem - C\C++ does not support dynamic sizing arrays. You need to specify a size for the array to allocation, otherwise you'll get memory block overruns.
here is my code, I can not figure out why it won't work as a function when the exact code in main() produces the correct answer. The assignment is to convert binary number to decimal.
#include <iostream>
#include <cstdlib>
#include "std_lib_facilities.h"
using namespace std;
int binaryCon(int biNum);
int main()
{
int num, bin, Bnum;
cout << "Enter the binary number(1s and 0s) : ";
cin >> num;
bin = num;
Bnum = binaryCon(num);
cout << "The decimal equivalent of " << bin << " : " << Bnum << endl;
}
int binaryCon(int biNum)
{
long dec = 0, rem = 0, base = 1;
enter code here`while (biNum > 0)
rem = biNum % 10;
dec = dec + rem * base;
base = base * 2;
biNum = biNum / 10;
return biNum;
}
corrected code:
#include <iostream>
#include <cstdlib>
using namespace std;
int binaryCon(int biNum);
int main()
{
int num, bin, Bnum;
cout << "Enter the binary number(1s and 0s) : ";
cin >> num;
bin = num;
Bnum = binaryCon(num);
cout << "The decimal equivalent of " << bin << " : " << Bnum << endl;
getchar();
return 0;
}
int binaryCon(int biNum)
{
long dec = 0, rem = 0, base = 1;
while (biNum > 0){
rem = biNum % 10;
dec = dec + rem * base;
base = base * 2;
biNum = biNum / 10;
}
return dec;
}
As you are not using { and } in your while loop may be its going in infinite loop. As its working for this line only
while (biNum > 0)
rem = biNum % 10; // running this line infinite as `biNum > 0`
Use
while (biNum > 0){
rem = biNum % 10;
dec = dec + rem * base;
base = base * 2;
biNum = biNum / 10;
}
maybe this?
while (biNum > 0)
{
rem = biNum % 10;
dec = dec + rem * base;
base = base * 2;
biNum = biNum / 10;
}
int main() or int main(int argc, char** argv) must return a value. If you return 0 then it means that there is no problem with code. Another numbers 1,2 etc means there is an error.(Returned numbers are error numbers)
Using Bottom to up DP approach, I am able to solve the problem How to solve http://www.spoj.com/problems/MST1/ upto 10^8.
If input is very large n upto 10^9. I will not be able to create lookup table for upto 10^9. So what will be better approach to solve the problem ?
Is there any heuristic solution ?
#include <iostream>
#include <climits>
#include <algorithm>
using namespace std;
int main()
{
const int N_MAX = 20000001;
int *DP = new int[N_MAX];
DP[1] = 0;
for (int i = 2; i < N_MAX; i++) {
int minimum = DP[i - 1];
if (i % 3 == 0) minimum = min(minimum, DP[i/3]);
if (i % 2 == 0) minimum = min(minimum, DP[i/2]);
DP[i] = minimum + 1;
}
int T, N; cin >> T;
int c = 1;
while (T--) {
cin >> N;
cout << "Case " << c++ << ": " << DP[N] << endl;
}
delete[] DP;
}