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#include <stdio.h>
#include <stdlib.h>
static void swap(int *x1, int *y1, int *x2, int *y2) {
	int t = *x1;
	*x1 = *x2;
	*x2 = t;
	t = *y1;
	*y1 = *y2;
	*y2 = t;
}
int main(void) {
	static int grid[1024][1024];
	int x1, y1, x2, y2;
	while (4 == scanf("%d,%d -> %d,%d\n", &x1, &y1, &x2, &y2)) {
		if (x1 != x2 && y1 != y2) continue;
		if (x2 < x1 || y2 < y1) swap(&x1, &y1, &x2, &y2);
		for (int y = y1; y <= y2; ++y)
		for (int x = x1; x <= x2; ++x) {
			grid[y][x]++;
		}
	}
	int points = 0;
	for (int y = 0; y < 1024; ++y)
	for (int x = 0; x < 1024; ++x) {
		if (grid[y][x] > 1) points++;
	}
	printf("%d\n", points);
}