Run ID:121506

提交时间:2025-06-07 15:17:12

#include<bits/stdc++.h> using namespace std; int main(){ int a; cin>>a; switch(a){ case 1: case 3: case 5: case 7: case 8: case 10: case 12: cout<<31 ; break; case 4: case 6: case 9: case 11: cout<<30; break; case 2: cout<<29 ; break; default: cout<<"Invalid." ; } return 0; }