HDU 1015 Safecracker

与其说这是一道搜索题，倒不如说是一道枚举题更加合适，反正就是纯暴力。。。。注意读懂题意

#include<iostream>
#include<stdio.h>
#include<string.h>
#include<math.h>
#include<string>
#include<algorithm>
using namespace std;
char s[12];
int cmp(const void*a ,const void*b)
{
    return *(int*)b-*(int*)a;
}
__int64 target;
int main(void)
{
    setbuf(stdout,NULL);
    while(scanf("%I64d %s",&target,s)!=EOF)
    {
        if(target==0 && strlen(s)==3)break;
        int v,w,x,y,z;
        int len=strlen(s);
        int flag=0;
        int* num=new int[len];
        for(v=0;v<len;v++)
        {
            num[v]=s[v]-'A'+1;
        }
        qsort(num,len,sizeof(num[0]),cmp);
        for(v=0;v<len;v++)
        {
            for(w=0;w<len;w++)
            {
                if(w==v)continue;
                for(x=0;x<len;x++)
                {
                    if(x==v||x==w)continue;
                    for(y=0;y<len;y++)
                    {
                        if(y==v||y==w||y==x)continue;
                        for(z=0;z<len;z++)
                        {
                            if(z==v||z==w||z==x||z==y)continue;
                            if(fabs(num[v]-num[w]*num[w]+pow(num[x],3)-pow(num[y],4)+pow(num[z],5)-target)<0.00001)//这点千万要注意，pow的 原型为double pow( double x, double y ); 
                            {
                                flag=1;
                                break;
                            }
                        }
                        if(flag)break;
                    }
                    if(flag)break;
                }
                if(flag)break;
            }
            if(flag)break;
        }
        if(flag==0)
        {
            printf("no solution\n");
            continue;
        }
        printf("%c%c%c%c%c\n",num[v]-1+'A',num[w]-1+'A',num[x]-1+'A',num[y]-1+'A',num[z]-1+'A');
    }
    return 0;
}