#include <stdio.h>

int main()
{
	char c;
	int lines = 0, ascii[128] = {0};

	while (lines < 2) {
		c = getchar();
		if (c == '\n' || c == EOF) {
			lines++;
		} else if (!ascii[(int)c]) {
			putchar(c);
			ascii[(int)c]++;
		}
	}

	return 0;
}