#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int a; cin>>a; switch(a){ case 1: cout<<31; break; case 2: cout<<29; break; case 3: cout<<31; break; case 4 : cout<<30; break; case 5: cout<<31; break; case 6: cout<<30; break; case 7: cout<<31; break; case 8: cout<<31; break; case 9: cout<<30; break; case 10: cout<<31; break; case 11: cout<<30; break; case 12: cout<<31; break; default: cout<<"lnvalid." } return 0; }