I am getting a runtime error in some test cases when I try to submit my code.

Problem Link: https://atcoder.jp/contests/dp/tasks/dp_a

My code:

```
#include<bits/stdc++.h>
using namespace std;
#define int long long
int minCost(int n, vector<int> h, vector<int> dp) {
if (dp[n] != -1) {
return dp[n];
}
if (n == 1) {
return dp[n] = 0;
}
if (n == 2) {
return dp[n] = abs(h[1] - h[2]);
}
int oneStep = minCost(n - 1, h, dp) + abs(h[n] - h[n - 1]);
int twoStep = minCost(n - 2, h, dp) + abs(h[n] - h[n - 2]);
if (oneStep < twoStep) {
return dp[n] = oneStep;
}
return dp[n] = twoStep;
}
int32_t main() {
int n;
cin >> n;
vector<int> h(n + 1);
for (int i = 1; i <= n; i++) {
cin >> h[i];
}
vector<int> dp(n + 1, -1);
cout << minCost(n, h, dp);
return 0;
}
```

i cannot figure out why it is giving runtime error. it works perfectly fine for sample tests.

Source: Windows Questions C++