#include <stdio.h>
const int BUFSIZE = 256;

int main(void){
    int i = 0;
    int j = 1;
    char buf[BUFSIZE];
    
    scanf ("%s", buf);
    
    while (j < BUFSIZE && buf[j] != '\0') {
        while (buf[i] - buf [j] == 0) {
            j++;
        }
        buf[++i] = buf[j];
    }
    buf[i++] = '\0';

    printf ("%s", buf);
    return 0;
}