Printing patterns using loop in python - python-3.x

My program read an integer number N, that correspond to the order of a Bidimentional array of integers, and build the Array according to the below example. I want to fill the middle elements like my expected output.
My code:
n = int(input())
for row in range(1, n+1):
for colum in range(1, n+1):
print(row, end=" ")
print()
Input:
5
My output:
1 1 1 1 1
2 2 2 2 2
3 3 3 3 3
4 4 4 4 4
5 5 5 5 5
The output I want:
1 1 1 1 1
1 2 2 2 1
1 2 3 2 1
1 2 2 2 1
1 1 1 1 1
I want to fill the middle elements like this. The height number at the middle then the second height number and so on..

for the "1-2-3-2-1" sequence, you can get it as the "minimum between row and n + 1 - row" - - min(row, n + 1 - row). (And the symmetrical for column) - and then
you print the min of this calculation for row and cols:
n = int(input())
for row in range(1, n+1):
for column in range(1, n+1):
mrow = min(row, n + 1 - row)
mcol = min(column, n + 1 - column)
print(min(mrow, mcol), end=" ")
print()

I hope this is not a homework question, but i will help you.
This can be done a lot more easily with lists!:
def cell_value(i, j, n_rows):
return min(
abs(i - -1),
abs(i - n_rows),
abs(j - -1),
abs(j - n_rows),
)
rows=int(input("Enter the number of rows:"))
row2 = [
[
cell_value(i, j, rows)
for j in range(rows)
]
for i in range(rows)
]
for r in row2:
print(*r)
Or it can be done even more easily like this below:
numberOfRows = int(input("Enter the number of rows:"))
listOut = [[1]*numberOfRows] * numberOfRows #grid of 1s of appropriate size
for j in range(int((numberOfRows+1)/2)): #symmetrical, so only look to the middle
if j > 0:
listOut[j] = list(listOut[j-1]) #copy previous row
for i in range(int((numberOfRows+1)/2)):
if i>=j:
listOut[j][i] = j+1
listOut[j][numberOfRows-(i+1)] = j+1
#copy current row to appropriate distance from the end
listOut[numberOfRows-(j+1)] = list(listOut[j])
for row in listOut:
print(row)
Both of the above programs give the SAME result
Enter the number of rows:5
1 1 1 1 1
1 2 2 2 1
1 2 3 2 1
1 2 2 2 1
1 1 1 1 1
Note:this is only possible for odd numbers!
Let me know if you have any doubts...
Cheers!

enter image description here
`for i in range(n):
````print((n-i)*" ",end=" ")
````print((i+1)*"* ")

Related

How to fill a matrix with equal sum of rows and columns?

I have a N x N matrix with integer elements.
We have two inputs : n and k.
There is two condition for solving this problem:
1- sum of matrix's columns and rows should be equal to k.
2- Difference between max and min numbers in matrix should be minimum.
I wrote a code in python but it doesn't work well.
n , k = map(int,input().split())
matrix = [[k//n]*n for i in range(n)]
def row_sum(matrix,row):
return sum(matrix[row])
def col_sum(matrix,col):
res = 0
for i in matrix:
res += i[col]
return res
for i in range(n):
for j in range(n):
if (row_sum(matrix,i) != k) and (col_sum(matrix, j) != k):
matrix[i][j] += 1
for i in matrix:
print(*i)
for example we have a 5x5 matrix that sum of its columns and rows should be equal to 6:
input : 5 6
output :
2 1 1 1 1
1 2 1 1 1
1 1 2 1 1
1 1 1 2 1
1 1 1 1 2
but it doesn't work well:
input : 6 11
output:
2 2 2 2 2 1
2 2 2 2 2 1
2 2 2 2 2 1
2 2 2 2 2 1
2 2 2 2 2 1
1 1 1 1 1 2
I spend a lot of time on this and i can't solve it. Please Help!
(This problem is not a homework or something like that. It's a question from an algorithm contest and the contest is over!)
The solution is to work out the first row (using the code you already have), and then set each row to be the row above it rotated one position.
So for example if the first row has the values
a b c d e
then you rotate one position each row to get
a b c d e
b c d e a
c d e a b
d e a b c
e a b c d
Since each value gets placed in each column once the columns will contain one of each value and so add up to the same total, and since each row has the same values just moved around all the rows add up the same too.
Code:
n , k = map(int,input().split())
matrix = [[k//n]*n for i in range(n)]
def row_sum(matrix,row):
return sum(matrix[row])
for j in range(n):
if (row_sum(matrix,0) != k):
matrix[0][j] += 1
for i in range(1, n):
for j in range(n):
matrix[i][j] = matrix[i-1][(j+1)%n]
for i in matrix:
print(*i)

Palindrome Matrix for the given n number

Output ExampleHow do I create a 2*n+1 matrix as mentioned below:
Input:
1
Output:
1 2 1
2 1 2
1 2 1
Input:
2
Output:
1 2 3 2 1
2 3 1 3 2
3 1 2 1 3
2 3 1 3 2
1 2 3 2 1
I had this code written. Hope it helps, just create a first row and then use that as reference for adding new rows.
INPUT = 3
MATRIX_DIM = (2 * INPUT) + 1
palindorme_matrix = []
current_value = 1
current_row = []
for idx in range(MATRIX_DIM):
current_row.append(current_value)
if idx >= (INPUT):
current_value -= 1
else:
current_value += 1
palindorme_matrix.append(current_row)
for row in range(1, MATRIX_DIM):
new_row = current_row.copy()
for i in range(len(current_row)):
new_row[i] += 1
if new_row[i] > (INPUT + 1):
new_row[i] = 1
palindorme_matrix.append(new_row)
current_row = new_row.copy()
print("Palindrome Matrix ", palindorme_matrix)

Given number n. Print numbers from 2 to n, next to each number write its divisors (except for the number itself)

Given number n. Print numbers from 2 to n, next to each number write its divisors (except for the number itself).
For example for n = 6(correct output):
2 - 1
3 - 1
4 - 1, 2
5 - 1
6 - 1, 2, 3
I solved the problem itself, or rather I could find the divisors for each number, but the difficulty comes out with the conclusion. Here is my code:
n = int(input("Введите число: "))
for i in range(2,n+1):
for j in range(1,i):
if i % j ==0:
print(f'{i} - {j}')
My output:
2 - 1
3 - 1
4 - 1
4 - 2
5 - 1
6 - 1
6 - 2
6 - 3
I don't know how to fix this. Can you, please, suggest with ignorance of what topic my error with the output is connected and how can I solve it?
By default print() puts a newline at the end. So you have to ignore this newline in your case.
n = int(input("Введите число: "))
for i in range(2,n+1):
print(f'{i} -', end = '')
for j in range(1,i):
if i % j ==0:
print(f' {j}', end = '')
print()

How to generate pyramid of numbers (using only 1-3) using Python?

I'm wondering how to create a pyramid using only element (1,2,3) regardless of how many rows.
For eg. Rows = 7 ,
1
22
333
1111
22222
333333
1111111
I've have tried creating a normal pyramid with numbers according to rows.
eg.
1
22
333
4444
55555
666666
Code that I tried to make a Normal Pyramid
n = int(input("Enter the number of rows:"))
for rows in range (1, n+1):
for times in range (rows):
print(rows, end=" ")
print("\n")
You need to adjust your ranges and use the modulo operator % - it gives you the remainer of any number diveded by some other number.Modulo 3 returns 0,1 or 2. Add 1 to get your desired range of values:
1 % 3 = 1
2 % 3 = 2 # 2 "remain" as 2 // 3 = 0 - so remainder is: 2 - (2//3)*3 = 2 - 0 = 2
3 % 3 = 0 # no remainder, as 3 // 3 = 1 - so remainder is: 3 - (3//3)*3 = 3 - 1*3 = 0
Full code:
n = int(input("Enter the number of rows: "))
print()
for rows in range (0, n): # start at 0
for times in range (rows+1): # start at 0
print( rows % 3 + 1, end=" ") # print 0 % 3 +1 , 1 % 3 +1, ..., etc.
print("")
Output:
Enter the number of rows: 6
1
2 2
3 3 3
1 1 1 1
2 2 2 2 2
3 3 3 3 3 3
See:
Modulo operator in Python
What is the result of % in Python?
binary-arithmetic-operations
A one-liner (just for the record):
>>> n = 7
>>> s = "\n".join(["".join([str(1+i%3)]*(1+i)) for i in range(n)])
>>> s
'1\n22\n333\n1111\n22222\n333333\n1111111'
>>> print(s)
1
22
333
1111
22222
333333
1111111
Nothing special: you have to use the modulo operator to cycle the values.
"".join([str(1+i%3)]*(1+i)) builds the (i+1)-th line: i+1 times 1+i%3 (thats is 1 if i=0, 2 if i=1, 3 if i=2, 1 if i=4, ...).
Repeat for i=0..n-1 and join with a end of line char.
Using cycle from itertools, i.e. a generator.
from itertools import cycle
n = int(input("Enter the number of rows:"))
a = cycle((1,2,3))
for x,y in zip(range(1,n),a):
print(str(x)*y)
(update) Rewritten as two-liner
from itertools import cycle
n = int(input("Enter the number of rows:"))
print(*[str(y)*x for x,y in zip(range(1,n),cycle((1,2,3)))],sep="\n")

how to store python console output in python variable

below is my code :
def combinationUtil(arr, n, r,index, data, i):
if(index == r):
for j in range(r):
print(data[j], end = " ")
print(" ")
return
if(i >= n):
return
data[index] = arr[i]
combinationUtil(arr, n, r, index + 1, data, i + 1)
combinationUtil(arr, n, r, index, data, i + 1)
def printcombination(arr, n, r):
data = list(range(r))
combinationUtil(arr, n, r, 0, data, 0)
var = []
pp = 5
r = 3
arr = []
for i in range(1, pp+1):
arr.append(i)
n = len(arr)
printcombination(arr, n, r)
it gives me this output:
1 2 3
1 2 4
1 2 5
1 3 4
1 3 5
1 4 5
2 3 4
2 3 5
2 4 5
3 4 5
1 2 3
1 2 4
1 2 5
1 3 4
1 3 5
1 4 5
2 3 4
2 3 5
2 4 5
3 4 5
i want to save this output as a variable in python
You have a combination utility routine that produces the output of interest.
If you were calling someone else's routine, you might need to assign
sys.stdout to an io.StringIO() to capture the output.
But as it stands, you have control over the source code,
so you can easily replace
for j in range(r):
print(data[j], end=' ')
print(' ')
with the following more convenient interface:
yield [data[j] for j in range(r)]
Then iterate, e.g.:
for row in combinationUtil(arr, n, r, 0, list(range(r)), 0):
print(row)
Cf itertools.

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