#include <stdio.h>

int main() {
    int math, Chinese, English;
    float average = 0.0f;

    while (scanf("%d %d %d", &math,&Chinese,&English) != EOF)
    {
        average = (math + Chinese + English) / 3.0;
        if (average >= 60) 
        {
            printf("NO\n");
        }
        else 
        {
            printf("YES\n");
        }
    }
    return 0;
}