Help me in solving MATADD problem

help
,
1

My issue

why runtime error?

My code

#include <stdio.h>
int main()
{
    int n,m;
    int a[100][100];
    int b[100][100];
    int c[100][100];
    scanf("%d",&n);
    scanf("%d",&m);
    int i,j;
    for(i=0;i<n;i++)
    for(j=0;j<m;j++)
    scanf("%d",&a[i][j]);
    for(i=0;i<n;i++)
    for(j=0;j<m;j++)
    scanf("%d",b[i][j]);
    for(i=0;i<n;i++)
    {
        for(j=0;j<m;j++)
        {
            c[i][j]=a[i][j]+b[i][j];
        }
    }
    for(i=0;i<n;i++)
    {
        for(j=0;j<m;j++)
        {
            printf("%d ",c[i][j]);
        }
        printf("\n");
    }
    return 0;
}

Learning course: Data structures & Algorithms lab
Problem Link: https://www.codechef.com/learn/course/muj-dsa-c/MUJDSAC09/problems/MATADD