C :

#include<stdio.h>
int main()
{
   int i,n,a[2000],b[2000],sum=0;
   scanf("%d",&n);
   for(i=0;i<n;i++)
      scanf("%d",&a[i]);
   for(i=0;i<n;i++)
      scanf("%d",&b[i]);
   for(i=0;i<n;i++)  
	  sum=sum+a[i]*b[i];
   printf("%d\n",sum);
   return 0;
}

C++ :

#include<bits/stdc++.h>
using namespace std;
int a[1005],b[1005];
int main()
{
	int n,sum=0;
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		cin>>a[i];
	}
	for(int i=1;i<=n;i++)
	{
		cin>>b[i];
	}
	for(int i=1;i<=n;i++)
	{
		sum=sum+a[i]*b[i];
	}
	cout<<sum;
	return 0;
}

Python :

# coding=utf-8
n = int(input())
a = list(map(int, input().split()))
b = list(map(int, input().split()))

result = sum([x*y for x, y in zip(a, b)])

print(result)