2023 4 19

#include<iostream>
using namespace std;
void speed(double a){
double v;
v=(a-95859)/2;
cout<<"汽车的车速为"<<v<<endl;
}
int main(){
int i,j;
double s;
int A[5]={0};
for(i=95860;i<100000;i++)
{
    int t=i;
    for(j=0;j<5;j++)
    {
        A[j]=t%10;
        t/=10;
    }
    if(A[0]==A[4]&&A[1]==A[3])
    {
        for(j=0;j<5;j++)
        {
            cout<<A[j];
        }
        break;
    }
}
s=A[4]*10000+A[3]*1000+A[2]*100+A[1]*10+A[0];
speed(s);
return 0;
}

#include<iostream>
#include<math.h>
using namespace std;
class clock{
private:
    int hour,minture,second;
public:
    clock(){}
    clock(int a,int b,int c){
    hour=a;
    minture=b;
    second=c;
    }
    ~clock(){}
    friend ostream & operator<<(ostream&out,clock&c){
    out<<c.hour<<"."<<c.minture<<"."<<c.second<<endl;
    return out;
    }
    friend istream & operator>>(istream&in,clock&c){
    in>>c.hour>>c.minture>>c.second;
    return in;
    }
    clock operator++(){
    this->second++;
    if(this->second==60){
    this->minture++;
    this->second=0;
    }
    if(this->minture==60){
    this->hour++;
    this->minture=0;
    }
    if(hour==24){
    this->hour=0;
    this->minture=0;
    this->second=0;
    }
    return *this;
    }
    clock operator--(int ){
        clock old=*this;
        this->second--;
        return old;
    /*this->second=--this->second;
    return *this;*/
    }
};
int main(){
    clock c1;
    cout<<"请输入时间"<<endl;
    cin>>c1;
    cout<<c1<<endl;
    cout<<++c1<<endl;
    cout<<c1--<<endl;
}