PROG-1050: Chemical Reactant

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

    int n,p;
    scanf("%d%d",&n,&p);
    vector <int> g[n+1];
    map < int , vector<int> > mp;
    for(int i=1;i<=n;i++){
        for(int j=0;j<p;j++){
            int x;
            scanf("%d",&x);
            g[i].push_back(x);
            if(j==0) mp[x].push_back(i);
        }
    }

    int product[p];
    for(int j=0;j<p;j++) {
        scanf("%d",&product[j]);
    }

    bool found;
    for(auto i:mp[product[0]]){
        found=true;
        for(int j=0;j<p;j++){
            if(product[j]!=g[i][j]) {
                found=false;
                break;
            }
        }
        if(found){
            printf("%d",i);
            return 0;
        }
    }

    for(int k=1;k<=n;k++){
        int x;
        x=product[0]-g[k][0];
        for(auto i:mp[x]){
            found=true;
            for(int j=0;j<p;j++) {
                if(g[k][j]+g[i][j]!=product[j]){
                    found=false;
                    break;
                }
            }
            if(found && k!=i) {
                if(k<i) printf("%d %d",k,i);
                else printf("%d %d",i,k);
                return 0;
            }
        }
    }

    printf("NO");

    return 0;
}