#include<iostream> #include<cstdio> #include<cstring> #include<cmath> #include<iomanip> using namespace std; int main() { int a; cin>>a; int a1,a2,a3,a4; a1=a%10;//个 a2=a/10%10;//十 a3=a/10/10%10;//百 a4=a/10/10/10%10;//千 cout<<a1*1000+a4*100+a3*10+a2<<endl; return 0; }