hdu 1716 排列2(stl next_permutation)

http://acm.hdu.edu.cn/showproblem.php?pid=1716

考到题目直接套 next_permutation 没有注意到0不能为首位 结果wa了一整天

输出结构也略有些小坑

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<cmath>
using namespace std;
int num[10];
int main()
{
    int mark=0;
    while(scanf("%d%d%d%d",&num[0],&num[1],&num[2],&num[3])!=EOF)
    {
        if(num[0]==0&&num[1]==0&&num[2]==0&&num[3]==0)  break;
        if(mark==1) printf("
");
        if(mark==0) mark++;
        
        sort(num,num+4);
        int first,i;
        while(num[0]==0)
        {
            next_permutation(num,num+4);
        }
        first=num[0];
        int flag=0;
        do
        {
            if(first!=num[0])
            {
                    first=num[0];
                    flag=0;
                    printf("
");
            }
            if(first==num[0]&&flag!=0)
            {
                printf(" ");
            }
            for(int i=0;i<4;i++) printf("%d",num[i]);
            flag++;
        }while(next_permutation(num,num+4));
        printf("
");
    }
    return 0;
}
View Code

离线处理

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<cmath>
using namespace std;
int num[10000][10];
int main()
{
    int coun=0;

    while(1)
    {
        scanf("%d%d%d%d",&num[coun][0],&num[coun][1],&num[coun][2],&num[coun][3]);
        if(num[coun][0]==0&&num[coun][1]==0&&num[coun][2]==0&&num[coun][3]==0)
        break;
        coun++;
    }

    for(int k=0;k<coun;k++)
    {
        sort(num[k],num[k]+4);
        int first,i;
        while(num[k][0]==0)
        {
            next_permutation(num[k],num[k]+4);
        }
        first=num[k][0];
        int flag=0;
        do
        {
            if(first!=num[k][0])
            {
                    first=num[k][0];
                    flag=0;
                    printf("
");
            }
            if(first==num[k][0]&&flag!=0)
            {
                printf(" ");
            }
            for(int i=0;i<4;i++) printf("%d",num[k][i]);
            flag++;
        }while(next_permutation(num[k],num[k]+4));
        printf("
");
        if(k!=coun-1)
            printf("
");
    }
    return 0;
}
View Code
原文地址:https://www.cnblogs.com/sola1994/p/4243411.html