HUD 1729 Stone Game(SG)

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <cstdlib>

using namespace std;

int sg(int s, int c)
{
int q = (int)(sqrt(s * 1.0));

while (q * q + q >= s)
{
q--;
}

if (c > q)
{
return s - c;
}
else
{
return sg(q, c);
}
}

int main()
{
int n;
int cas = 0;
while (~scanf("%d", &n) && n)
{
printf("Case %d:\n", ++cas);

int ans = 0;

while (n--)
{
int s, c;
scanf("%d%d", &s, &c);

ans = ans ^ sg(s, c);
}

if (ans)
{
printf("Yes\n");
}
else
{
printf("No\n");
}
}
}