根据 log(a^b) = b*log(a),可以将溢出的值转换成范围内的值
#include <cstdio>
#include <algorithm>
#include <cmath>
#define eps 1e-8
using namespace std;
int a , b , c , d;
int main ( )
{
while ( ~scanf ( "%d%d%d%d" , &a , &b , &c , &d ) )
{
double num1 = b*1.0*log(a*1.0);
double num2 = d*1.0*log(c*1.0);
if ( fabs ( num1 -num2 ) < eps ) puts ("=");
else if ( num1 > num2 + eps ) puts ( ">" );
else puts ( "<" );
}
}