#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<iomanip> #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ int a,g,s,b,q; cin>>a; g=a%10; s=a%10; b=a/100%10; q=a/1000; cout<<b*1000+q*100+g*100+s; return 0; }0