[C++]백준 2839번:설탕 배달

https://www.acmicpc.net/problem/2839

#include <iostream>

using namespace std;

int main() {

int N, exit;

int a, b, min;

exit= a = b= 0;

cin >> N;

a = N / 5;

min = b = N / 3;

for (int i = 0; i <= a; i++)

for (int j = 0; j <= b; j++)

if (N == (5 * i) + (3 * j)) {

if ((i + j) < min)

min = i + j;

exit++;

}

if (exit >= 1)

cout << min << endl;

else

cout << "-1" << endl;

}