#include <iostream>
using namespace std;
int main() {
    int sum = 0;
    // 目标：求长度为5的数组arr所有元素的和
    int arr[5] = {2,4,6,8,10};
    for(int i = 0; i <= 5; i++) {
        sum += arr[i];
    }
    cout << sum << endl;
    return 0;
}