#include <stdio.h>

int main(){
	int result = 0;
	int value = 0;
	int vxod[999];
	int a = 0;
	//int b = 999;
	for(int i = 0; i < 999; i++)
		vxod[i] = 0;
	for(int i = 0; i < 999; i++){
		scanf("%d",&value);
		vxod[i] = value;
	}
	for(int i = 0; i < 999; i++){
		if(vxod[i] > 0)
			a++;
	}
	for(int i = 1; i < a; i++){
		result = vxod[0] * result + vxod[i];
	}
	printf("Vysledok je: %d.00\n", result);
	return 0;
}