#include <stdio.h> int main() { int nu; scanf("%d", &nu); int q= nu/ 1000; int b = (nu / 100) % 10; int s = (nu / 10) % 10; int g = nu% 10; int n = b * 1000 + q * 100 + g * 10 + s; printf("%d\n", n); return 0; }