Project Euler problem 44

#include <iostream>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <cstdlib>
#include <stack>
#include <cmath>
#define eps 1e-6
#define INF 1000000007
#define PI acos(-1.0)
using namespace std;
bool ok(int x)
{
x = x * 12 + 1;
int m = (int)sqrt(x * 1.0);
if(m * m == x && (m + 1) % 6 == 0) return 1;
return 0;
}
bool gao(int x)
{
int m = (int)sqrt(x * 1.0);
for(int i = 2; i <= m; i++)
{
if(x % i == 0)
{
int t = x / i;
if((t + 1) % 3 != 0) continue;
if(t - 3 * i + 1 < 6) break;
int k1 = (t + 1) / 3;
int k2 = i;
if((k1 + k2) % 2 == 1 || k1 <= k2) continue;
int a = (k1 + k2) / 2;
int b = (k1 - k2) / 2;
if(ok(3 * (a * a + b * b) - a - b)) return 1;
}
}
return 0;
}
int main()
{
for(int i = 5;  ; i++)
{
if(gao(i * (3 * i - 1)))
{
cout << i * (3 * i - 1) / 2 << endl;
break;
}
}
return 0;
}