Submission #3050284

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Source Code Expand

#include<iostream>
using ll = long long;
using namespace std;
int main(){
    string str;
    cin>>str;
    int cnt=0,ans=1;
    for(int i=0;i<str.size();i++){
        if(str[i]=='2') cnt++;
        else cnt--;
        ans = max(ans,cnt);
        if(cnt<0){
            cout << "-1\n";
            return 0;
        }
    }
    if(cnt!=0){
        cout << "-1\n";
        return 0;
    }
    cout << ans << endl;
    return 0;
}

Submission Info

Judge Result