#include <stdio.h>

int main(){
    int x,y,i,j,k,n;
    printf("Enter the size of key matrix: ");
    scanf("%d", &n);

    printf("Enter the key matrix: ");
    int a[n][n];
    for(i=0; i<n; i++){
        for(j=0; j<n; j++){
            scanf("%d", &a[n][n]);
        }
    }
    printf("Enter the message to encrypt: ");
    char s;
    scanf("%c", &s);

    int temp = (n - sizeof(s)%n)%n;
    for(i=0; i<temp; i++){
        s+='x';
    }
    k=0;
    char ans;
    while(k < sizeof(s)){
        for(i=0; i<n; i++){
            int sum = 0;
            int temp[] = {k};
            for(j=0; j<n; j++){
                sum += (a[i][j] % 26 * (s[temp++] - 'a')%26)%26;
                sum = sum % 26;
            }
            ans+=(sum+'a');
        }
        k+=n;
    }
    printf("%c", ans);

    return 0;
}