#include <stdio.h>
#include <stdlib.h>
short main(void)
{
	char tf[] = "TF";
	short t;
	scanf("%hd", &t);
	short *x = malloc(sizeof(short)*t);
	for (short i = 0; i < t; i++) scanf("%hd", &x[i]);
	short p = 0;
	short xorf = 0;
	for (short i = 0; i < t; i++) {
		if (!(p == x[i] + 1 || p == x[i] - 1)) xorf = 1;
		p = x[i];
	}
	printf("%c\n", tf[xorf]);
	return 0;
}