#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,b,c,d,e; cin>>a; b=a/1000; c=a/100%10; d=a/10%10; e=a%10; cout<<c*1000+b*100+e*10+d; return 0; }