两种方法上号

Switch

#include <iostream>
using namespace std;
int main(){
    int n;
    cin>>n;
    switch(n){
        case 1:cout<<"Monday";break;
        case 2:cout<<"Tuesday";break;  
        case 3:cout<<"Wednesday";break;  
        case 4:cout<<"Thursday";break;      
        case 5:cout<<"Friday";break; 
        case 6:cout<<"Saturday";break;  
        default:cout<<"Sunday";break;    
    }  
    return 0;
}

if

#include <bits/stdc++.h>
using namespace std;
int main(){
    int a;
    cin >> a;
    if (a==1){
        cout << "Monday";
    }
    if (a==2){
        cout << "Tuesday";
    }
    if (a==3){
        cout << "Wednesday";
    }
    if (a==4){
        cout << "Thursday";
    }
    if (a==5){
        cout << "Friday";
    }
    if (a==6){
        cout << "Saturday";
    }
    if (a==7){
        cout << "Sunday";
    }
    return 0;
}