#include <stdio.h>
#include<stdlib.h>
int main(){
	int*p1,*p2,i,n,product=0;
	scanf("%d", &n);
	p1 = (int*)malloc(n * sizeof(int));
	p2 = (int*)malloc(n * sizeof(int));//动态内存分配
	scanf("%d", &n);
	for (i = 0; i < n; i++) {
		
			scanf("%d", &p1[i]);
		
	}
	for (i = 0; i <= n; i++) {
		
			scanf("%d", &p2[i]);
		
	}
	for (i = 0; i < n; i++) {
		product += p1[i] * p2[i];
	}
	printf("%d", product);
	free(p1);
	free(p2);
	return 0;
}