#pragma GCC optimize(2)
#pragma GCC optimize(2)
#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>

using namespace std;

void read( __int128 &x )
{
    x = 0; int f = 1;
    char c ; c = getchar();
    while ( c < '0' && c > '9' ) { if ( c == '-' ) f = 1; c = getchar();}
    while ( c >= '0' && c <= '9' ) x = (x << 3) + (x << 1) + (c ^ 48), c = getchar();
    x *= f;
}

void print( __int128 x )
{
    if ( !x ) return ;
    if ( x < 0 ) putchar('-'), x = -x;
    print(x / 10);
    putchar(x % 10 + '0');
}

// 上面的两个函数可以忽略

int main()
{
    __int128 n = 20;
    int i;
    while ( cin >> i ) n -= i;
    print(n);
    return 0;
}