Tuesday, 10 September 2019

The Joy of Computing using Python: Programming Assignments 1,2 & 3

                3 comments   
1. A Lower triangular matrix is a square matrix (where the number of rows and columns are equal)  where all the elements above the diagonal are zero.
For example, the following is an upper triangular matrix with the number of rows and columns equal to 3.

1 0 0
4 5 0
7 8 9

Write a program to convert a square matrix into a lower triangular matrix.

Input Format:The first line of the input contains an integer number n which represents the number of rows and the number of columns.
From the second line, take n lines input with each line containing n integer elements. Elements are separated by space.

Output format:
Print the elements of the matrix with each row in a new line and each element separated by a space.

Example 1:

Input:
3
1 2 3
4 5 6
7 8 9

Output:
1 0 0
4 5 0
7 8 9

Example 2:

Input:
4
12 2 5 6
10 11 4 1
32 1 4 10
1 2 10 9

Output:
12 0 0 0
10 11 0 0
32 1 4 0
1 2 10 9

Program:

n=int(input())
l=[]
for i in range(n):
    for j in range(1):
        temp=[int(g) for g in input().split()]
        l.append(temp)


for i in range(n):
    for j in range(n):
        if i<j:
            if j==n-1:
                print(0,end="")
            else:
                print(0,end=" ")
        else:
            if j==n-1:
                print(l[i][j],end="")
            else:
                print(l[i][j],end=" ")
        
    if i!=n-1:
      print()

2. Given a square matrix of N rows and columns, find out whether it is symmetric or not.

Input Format:The first line of the input contains an integer number n which represents the number of rows and the number of columns.
From the second line, take n lines input with each line containing n integer elements with each element separated by a space.

Output Format:
Print 'YES' if it is symmetric otherwise 'NO'

Example:

Input:
2
1 2
2 1

Output:
YES

Program:

n=int(input())
l=[]
for i in range(n):
    for j in range(1):
        temp=[int(g) for g in input().split()]
        l.append(temp)
x=0
for i in range(n):
    for j in range(n):
        if l[i][j]!=l[j][i]:
           x=x+1
if x==0:
  print("YES",end="")
else:
  print("NO",end="")

3. Given a matrix with N rows and M columns, the task is to check if the matrix is a Binary Matrix. A binary matrix is a matrix in which all the elements are either 0 or 1.

Input Format:The first line of the input contains two integer number N and M which represents the number of rows and the number of columns respectively, separated by a space.
From the second line, take N lines input with each line containing M integer elements with each element separated by a space. 

Output Format:
Print 'YES' or 'NO' accordingly

Example:

Input:
3 3
1 0 0
0 0 1
1 1 0

Output:
YES

Program:

n,m=map(int,input().split())
b=0

for i in range(n):
    for j in range(1):
        temp=[int(g) for g in input().split()]
        for k in temp:
            if k!=0 and k!=1:
                b=b+1
                break

if b==0:
    print("YES",end="")
else:
    print("NO",end="")

3 comments: