(除法)Division UVA - 725

题目链接：Division UVA - 725

思路：枚举0~9的所有排列？没这个必要。只需要枚举fghij就可以计算出abcde，然后判断是否所有数字都不相同即可。不仅程序简单，而且枚举量也从10！=3628800降低至不到1万，而且abcde和fghig加起来超过10位时可以终止枚举。由此可见，即使采用暴力枚举，也是需要认真分析问题的。

代码：

#include<iostream>
#include<string>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<queue>
#include<stack>
#include<map>
#include<iomanip>
#define ll long long

using namespace std;
const int maxn = 99999 + 5;

bool solve(int s, int v){
int vis[10];
memset(vis, 0, sizeof(vis));
int a = 0, b = 0, c = 0, d = 0, e = 0,f = 0,g = 0,h = 0,i = 0,j = 0;
e = s%10; s /= 10; j = v%10; v/=10;
d = s%10; s /= 10; i = v%10; v/=10;
c = s%10; s /= 10; h = v%10; v/=10;
b = s%10; s /= 10; g = v%10; v/=10;
a = s%10; f = v%10;
vis[a]++;vis[b]++;vis[c]++;vis[d]++;vis[e]++;vis[f]++;vis[g]++;vis[h]++;vis[i]++;vis[j]++;
bool kk = true;
for(int i = 0; i < 10; i++) if(vis[i] != 1) {
kk = false;
break;
}

if(kk) return true;
else return false;
}
int main()
{
int n, caset = 0;
while(1) {
scanf("%d",&n);
if(n == 0) break;
if(caset++) cout << endl;
bool f = false;
for(int i = 1023;i < maxn; i++) {
int sum = i*n;
if(sum > maxn) break;
if(solve(sum, i)) {
printf("%05d / %05d = %d\n", sum, i, n);
f = true;
}
}
if(!f) printf("There are no solutions for %d.\n", n);
}
return 0;
}