HDU 1060 Leftmost Digit 数学题

#include<stdio.h>
#include<string.h>
#include<math.h>
#define lld __int64
int main()
{
int i, j, cas;
int n;
scanf("%d", &cas);
while(cas--)
{
scanf("%d", &n);
double sum1 = n*log10(n*1.0);
lld sum2 = (lld) sum1;
sum1 -= sum2;
printf("%d\n", (int)pow(10.0, (double)sum1));
}
return 0;
}