I was trying to solve 732D and after struggling with an optimal algorithm for sometime, I looked into the accepted solutions and saw that many ACs were as simple as the following.
http://codeforces.me/contest/732/submission/21571861
#include<bits/stdc++.h>
using namespace std;
int main()
{
int n,m;
cin>>n>>m;
int arr[n+1];
for(int i=1;i<=n;i++)cin>>arr[i];
int sum=m,x;
for(int i=0;i<m;i++){cin>>x; sum+=x;}
for(int i=sum;i<=n;i++)if(arr[i]){cout<<i; return 0;}
cout<<-1;
}
I think they will fail on a simple testcase as —
8 2
1 1 1 1 1 1 1 2
1 1
( The ans should be 8 )
Am I understanding the question incorrectly ?
UPDATE It seems like after the contest, some test cases might have been updated/added covering the case above.