Submission #704451

#	Time	Username	Problem	Language	Result	Execution time	Memory
704451		delrey	Lun (COCI19_lun)	C++14	40 / 50	1 ms	300 KiB

lun

#include <bits/stdc++.h>

using namespace std;

int main()
{
    int n;
    string s;
    cin>>n>>s;
    int x = 0;
    while(s[x] != 'x')
        x++;
    int sum = 0;
    for(int i = n - 2; i >= 0; i--)
    {
        if(s[i] == 'x')
            continue;
        int a = s[i] - '0';
        if((n - 2 - i) % 2 == 0)
        {
            a *= 2;
            if(a > 9)
                a = a / 10 + a % 10;
        }
        sum += a;
        //cout<<a<<" ";
    }
    //cout<<endl<<sum<<" ";
    sum *= 9;
    sum %= 10;
    //cout<<sum<<" "<<endl;
    if(x == n - 1)
    {
        cout<<sum<<endl;
        return 0;
    }
    for(int a = 0; a < 10; a++)
    {
        int sum2 = sum;
        sum2 = (sum2 + ((a * 9) % 10)) % 10;
        if(sum2 == s[n - 1] - '0')
        {
            cout<<a<<endl;
            return 0;
        }
    }
    return 0;
}

• Subtask 1: 40 / 50