Submission #2405910

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Source Code Expand

#include <iostream>
#include <bits/stdc++.h>

typedef long long ll;
const int MAXN=1e6+7;

using namespace std;
int c[MAXN+5];
int main()
{
    string s,t;
    int n;
    cin>>n;
    cin>>s>>t;
    if(s[0]!=t[0]|| s.length()!=t.length()){return 0*puts("-1");}
    int ans=0,k=0,sum=0;
    for(int i=n-1,j=n-1;i>=0;i--)
    {
        sum+= c[i+k];
        if( j>i || t[i]!=s[j])
        {
            while( j&&( j>i|| t[i]!=s[j])) j--;
            if(j==i) continue;
            if(j<0)
            {
                return 0*puts("-1");
            }
            k++,sum++;
            c[i+k]=0,c[j+k]--;
        }
        ans=max(ans,sum);
    }
    cout<<ans<<endl;
    return 0;
}

Submission Info

Judge Result