FIXING TYPOS CODEFORCES STRINGS
#include <bits/stdc++.h> using namespace std ; int main () { char a , b = 0 , c = 1 , d = 2 ; while ( cin >> a ){ if ( ! ( a == b && b == c ) && ! ( a == b && c == d )){ cout << a ; d = c ; c = b ; b = a ; } } }