#include <iostream>
#include <cmath>
using namespace std;
 
int main() {
    int a, b, c;
    cin >> a >> b >> c;
    int minFloor = min(min(a, b), c);
    int maxFloor = max(max(a, b), c);
    int middleFloor = a + b + c - minFloor - maxFloor;
    int resultFloor;
    if(31 * (maxFloor - minFloor) < 47 * (middleFloor - minFloor)){
        resultFloor = minFloor;
    }
    else{
        resultFloor = middleFloor;
    }
    cout << resultFloor;
    return 0;
}