View difference between Paste ID: J5fkYCux and bn10DthY

 #include <bits/stdc++.h>
 #include <ext/pb_ds/assoc_container.hpp>
 
 using namespace __gnu_pbds;
 using namespace std;
 
 //#define int long long
 #define ll long long
 gp_hash_table<ll, int> mp;
 
 int P=179,mod=1791791791;
 
 void calc(vector<int> &h,string &s){
     h.resize(s.size()+1,0);
 
     for(int i=1;i<=s.size();i++){
         h[i]=((ll)h[i-1]*P+(s[i-1]-'a'+1))%mod;
     }
 }
 
 void getP(vector<int> &p,int n){
     p.resize(n+1,1);
 
     for(int i=1;i<p.size();i++){
         p[i]=((ll)p[i-1]*P)%mod;
     }
 }
 
 int res(int l,int r,vector<int> &h,vector<int> &p){
     return ((ll)h[r+1]+mod-((ll)h[l]*p[r-l+1])%mod)%mod;
 }
 
 signed main() {
 
     ios::ios_base::sync_with_stdio(false);
     cin.tie(0);
     cout.tie(0);
 
     int n,m;
     cin>>n>>m;
 
     vector<string> a(n);
     vector<vector<int> > h(n),sm(n+1,vector<int> (m+1,0));
     vector<int> p;
 
     for(int i=0;i<n;i++){
         cin>>a[i];
         calc(h[i],a[i]);
         for(int j=1;j<=m;j++){
             sm[i+1][j]=sm[i][j]+sm[i+1][j-1]-sm[i][j-1]+(a[i][j-1]-'a'+1);
         }
     }
 
     getP(p,max(n,m));
 
     vector<vector<int> > dp(n,vector<int> (m,0));
     int k;
     pair<int,int> ans1={-1,-1};
     pair<int,int> ans2={-1,-1};
     for(k=1;k<=min(n,m);k++){
         bool check=false;
         mp.clear();
         for(int i=0;i<n-k+1;i++){
             for(int j=0;j<m-k+1;j++){
                 int r=j+k,b=i+k-1;
                 int sum=sm[b][r]-sm[i][r]-sm[b][r-1]+sm[i][r-1];
                 dp[i][j]=(((ll)dp[i][j]*P*P)%mod+(ll)res(j,j+k-1,h[i+k-1],p)+sum)%mod;
                 int res=mp[dp[i][j]];
                 if(res!=0){
                     ans1=make_pair(res/1000,res%1000);
                     ans2=make_pair(i+1,j+1);
                     check=true;
                 }
                 mp[dp[i][j]]=(ll)((i+1)*1000+(j+1));
             }
         }
 
         if(!check){
             break;
         }
     }
 
     if(k-1==0){
         cout<<0;
         return 0;
     }
     cout<<k-1<<endl;
     cout<<ans1.first<<" "<<ans1.second<<endl;
     cout<<ans2.first<<" "<<ans2.second<<endl;
 
 }