#include<stdio.h>
#include<string.h>
#include<math.h>
#include<stdlib.h>
int max(int a, int b) {
	if (a > b) {
		return a;
	}
	else {
		return b;
	}
}
int main() {
	int a, b,c,d,e;

	while (scanf("%d %d %d %d %d", &a, &b, &c, &d, &e) != EOF) {
		int  v = 0;
		if (d >= e) {
			int v1 = (a - 2 * d) * (b - 2 * d) * (c - 2 * d);
			int v2 = e * e * (4 * a + 4 * (b - 2 * e) + 4 * (c - 2 * e));
			v = max(v1, v2);
		}
		else {
			v = a * b * c - (2 * (d * (a - 2 * e) * (c - 2 * e)) + 2 * (d * (a - 2 * e) * (b - 2 * e)) + 2 * (d * (b - 2 * e) * (c - 2 * e)));
		}
		printf("%d\n", v);
	}
}