#include int main(void){ int N, i, j, tmp, result = 0; scanf("%d", &N); for (i = 0; 5 * i <= N; i++){ for (j = 0; j <= i ; j++){ tmp = N - 5*i - 2*j; if (tmp % 3 == 0 && tmp >= 0) result++; } } printf("%d", result); return 0; }