#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void)
{
	int val[2];
	char str[32], *ch;
	fgets(str, sizeof(str), stdin);
	ch = strtok(str, " \n");
	if (ch != NULL) val[0] = atoi(ch);
	ch = strtok(NULL, " \n");
	if (ch != NULL) val[1] = atoi(ch);
	ch = strtok(NULL, " \n");
	printf("%d\n", -(-val[0] - val[1]));
	return 0;
}