#include <stdio.h>

#define SPACE ' '

int main(void)
{
    int space = 0;

    int c;
    while ((c = getchar()) != EOF) {
        if (c == SPACE) {
            if (space == 0) {
                ++space;
                putchar(c);
            } else if (space > 0) {
                ++space;
            }
        } else {
            space = 0;
            putchar(c);
        }
    }

    return 0;
}