POJ ( acm.pku.edu.cn ) 1001

#include<stdio.h>
#include<string.h>
#define MAX 1024
void power(int *a, int base, int n)
{
   int i,j,r=0;
   memset(a, 0, sizeof(int)*MAX);
   for(i=0,j=base;j&&i<MAX;++i,j/=10)
       a[i]=j%10;
   for(i=0; i<n-1; ++i){
       j=0;
       for (j=0; j<MAX; j++){
           r+=a[j]*base;
           a[j]=r%10;
           r/=10;
       }
   }
}

int main() {
   char s[MAX];
   int a[MAX];
   int n, i, base, len, k;
   while(scanf("%s%d",&s,&n)!=EOF){
       base = 0;
       len = strlen(s);
       for (i=0; i<len; i++){
           if (s[i]=='.'){
               k = 6-(i+1);    //小数位数
               continue;
           }
           base*=10;base+=s[i]-'0';
       }
       for (i=5; s[i]=='0'; --i,--k)
           base/=10;
       k = k*n;
       power(a, base, n);
       for (i=MAX-1; i>=0; --i)
           if(a[i])
               break;
       if (k>i){
           printf(".");
           for (i=k-1; i>=0; --i)
               printf("%d", a[i]);
       }else{
           for (;i>=k;--i)
               printf("%d", a[i]);
           if (k!=0)
               printf(".");
           for (;i>=0;i--)
               printf("%d",a[i]);
       }
       printf("\n");
   }
   return 0;
}