Help me in solving ICL16A problem

help
,
1

My issue

I didn’t understood the problem. Can You give the related rosources?

My code

#include<bits/stdc++.h>
using namespace std;
int n,m;
int main()
{

    cin>>n>>m;
    vector<vector<char>>r(n, vector<char>(m));
    
    for(int i=0; i<n; i++)
        for(int j=0; j<m; j++)
            cin>>r[i][j];

    int mxx=-1;
    for(int i=0; i+1<n; i++)
        for(int j=0; j<m; j++)
        {
            int temp=abs(r[i+1][j]-r[i][j]);
            mxx= max(mxx, temp);
        }
    cout<<mxx<<endl;

    return 0;
}

Problem Link: ICL16A Problem - CodeChef