Discription
NB : An upper triangular matrix is a triangular matrix with all elements equal to 0 below the main diagonal.
Sample input 1:
3
1 2 3
0 5 6
0 0 9
Sample output 1:
Yes
Sample input 2:
3
1 1 1
1 0 0
0 0 0
Sample output 2:
No
C Program
#include <stdio.h>
int main()
{
int n;
scanf("%d",&n);
int mat[n][n];
for(int i = 0 ; i<n ; i++){
for(int j = 0 ; j<n ; j++){
scanf("%d",&mat[i][j]) ;
}
}
int flag = 1;
for(int i = 0 ; i<n ; i++){
for(int j = 0 ; j<i ; j++){
if(mat[i][j] != 0){
flag = 0;
break;
}
}
if(flag == 0)
{
break;
}
}
if(flag == 1)
{
printf("Yes");
}
else
{
printf("No");
}
return 0;
}
C++ Program
#include <bits/stdc++.h>
using namespace std;
int main()
{
int n;
cin>>n;
int mat[n][n];
for(int i = 0 ; i<n ; i++){
for(int j = 0 ; j<n ; j++){
cin>>mat[i][j];
}
}
bool flag = true;
for(int i = 0 ; i<n ; i++){
for(int j = 0 ; j<i ; j++){
if(mat[i][j] != 0){
flag = false;
break;
}
}
if(!flag)
{
break;
}
}
if(flag)
{
cout<<"Yes";
}
else
{
cout<<"No";
}
return 0;
}
JAVA Program
import java.util.*;
import java.lang.*;
import java.io.*;
class Main
{
public static void main (String[] args) throws java.lang.Exception
{
Scanner sc=new Scanner(System.in);
int n = sc.nextInt();
int mat[][] = new int[n][n];
for(int i = 0 ; i<n ; i++){
for(int j = 0 ; j<n ; j++){
mat[i][j] = sc.nextInt();
}
}
boolean flag = true;
for(int i = 0 ; i<n ; i++){
for(int j = 0 ; j<i ; j++){
if(mat[i][j] != 0){
flag = false;
break;
}
}
if(!flag)
{
break;
}
}
if(flag)
{
System.out.println("Yes");
}
else
{
System.out.println("No");
}
}
}
PYTHON Program
def IsUpperTri(a):
for i in range(1, len(a)):
for j in range(0, i):
if(a[i][j] != 0):
return False
return True
a = [[1,2,3],
[0,5,6],
[0,0,9]];
if IsUpperTri(a):
print ("Yes")
else:
print ("No")
