UVa 729 The Hamming Distance Problem【枚举排列】

题意：给出数组的长度n,给出h，表示这个数组里面含有h个1，求其所有的排列

用next_permutation就可以了

#include<iostream>  
#include<cstdio>  
#include<cstring> 
#include <cmath> 
#include<stack>
#include<vector>
#include<map> 
#include<set>
#include<queue> 
#include<algorithm>  
using namespace std;

#define foreach(i,c) for (__typeof(c.begin()) i = c.begin(); i != c.end(); ++i)

typedef long long LL;
const int INF = (1<<30)-1;
const int mod=1000000007;
const int maxn=100005;

int p[maxn];

int main(){
    int T;
    scanf("%d",&T);
    while(T--){
        
        int n,h;
        scanf("%d %d",&n,&h);
        
        for(int i=0;i<n;i++){
            if(i<h) p[i]=1;
            else p[i]=0;
        }
        
        sort(p,p+n);
        
        do{
            for(int i=0;i<n;i++) printf("%d",p[i]);
            printf("
");
        }while(next_permutation(p,p+n));
        
        if(T)  printf("
");
    }
    return 0;
}