找出数组中超出总数1/4的数字

#include <iostream>
//上一题的扩展，有3个数字出现次数超过1/4。
using namespace std;
void Grial(int a[], int n)
{
if (n <= 3)return;
int count1=0, key1=0;
int count2=0, key2=0;
int count3=0, key3=0;
for (int i = 0; i < n; i++)
{
if (!count1 && key2 != a[i] && key3 != a[i])
{
count1++;
key1 = a[i];
}
else if (key1 == a[i])
{
count1++;
}
else  if (key2!=a[i] && key3!=a[i])
{
count1--;
}

if (!count2 &&key3 != a[i] && key1!=a[i])
{
count2++;
key2 = a[i];
}
else if (key2 == a[i])
{
count2++;
}
else if (key1!=a[i] && key3!=a[i])
{
count2--;
}

if (!count3 && key1!=a[i] && key2!=a[i])
{
count3++;
key3 = a[i];
}
else if (key3 == a[i])
{
count3++;
}
else if (key1!=a[i] && key2!=a[i])
{
count3--;
}

}
cout << key1 << endl;
cout << key2 << endl;
cout << key3 << endl;
}
int main()
{
int a[] = {1,5,5,5,5,2,3,1,2,2,1,1,1,2};
Grial(a, sizeof(a) / sizeof(int));
return 0;
}