#include <stdio.h>

int main(int argc, char **argv) {
	int c, i = 0;

	for (c = getchar(); c != EOF; c = getchar()) {
		if (c == '\n') {
			i = 0;
		} else {
			i++;
			if (i == 21) {
				putchar('\n');
				i = 1;
			}
		}
		putchar(c);
	}

	return 0;
}