#include <stdio.h>

/* line output frequency */
const int DIVISOR = 2;

int main() {
	char c;
	char newline = 1; /* a flag to mark newlines */
	char line_num = 0; 
	while (scanf("%c", &c)) {
		/* quit when 'Q' is met right after a newline */
		if (c == 'Q' && newline) break;

		/* Check to see whether to output this character or not */
		if (line_num % DIVISOR == 0)
			printf("%c", c);

		/* mark a new line */
		newline = (c == '\n') ? 1 : 0;

		if (newline) line_num++;
	}
	return 0;
}