Project Euler #73

20121003.cpp

#include<iostream>

using namespace std;

int gcd(int a,int b) {
    if(a == b) return a;
    if(a < b) return gcd(a,b-a);
    if(a > b) return gcd(a-b,b);
}

int main () {
    int MAX = 12000;
    float a = 1.0/3,b = 1.0/2;

    int count = 0;
    for(float i=2;i <= MAX;i++) {
        for(float j=1;j < MAX;j++) {
            if(i <= j) continue;
            if(j/i <= a || j/i >= b || (j == 1 && i == 3)) continue;
            if(gcd(i,j) == 1) count++;
        }
    }
    cout << count << endl;
}