日期问题

一个函数判断日期是否合法，一个函数用来输出。思路比较简单，枚举即可
注意还要按时间顺序输出，并不是每一个都对应三个输出！

C++ 代码

#include<iostream>
#include<cstring>
#include<algorithm>

using namespace std;
int days[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
bool check(int year,int month,int day)
{
    if(month==0||month>12)return false;
    if(day==0||month!=2&&day>days[month])return false;
    if(month==2){
        int leap= year%400==0 || year%4==0&&year%100!=0;
        if(day>28+leap)return false;
    } 
    return true;
}
void print(int year,int month,int day){
    if(year>=60)cout<<"19"<<year<<"-";
    else if(year>=10) cout<<"20"<<year<<"-";
    else  cout<<"200"<<year<<"-";
    if(month<10)cout<<"0"<<month<<"-";
    else cout<<month<<"-";
    if(day<10)cout<<"0"<<day<<"\n";
    else cout<<day<<"\n";
    return;
}
int main()
{
    int a,b,c;
    scanf("%d/%d/%d",&a,&b,&c);
    if(a==b&&a==c){//02/02/02只输出一个 
        print(a,b,c);return 0;
    }
    int ta=0,tb=0,tc=0;
    if(a>c)ta=a,tb=b,tc=c,swap(a,c);
    if(check(a,b,c))print(a,b,c);
    if(ta){//12/12/06只输出两个 
        if(check(ta,tb,tc))print(ta,tb,tc);
        return 0;
    }
    if(a>b)swap(a,b);
    if(check(c,a,b))print(c,a,b);

    if(check(c,b,a))print(c,b,a);

    return 0;
}