# Fair Pay - Amazon Top Interview Questions

### Problem Statement :

```You are given a list of integers ratings representing the performance scores of programmers. The manager would like to give \$1 to every programmer except if two programmers are adjacent, they'd like to pay the better performing programmer at least \$1 higher than the worse performing one.

Return the minimum amount of dollars the manager can pay following above constraints.

Constraints

n ≤ 100,000 where n is the length of ratings.

Example 1

Input

ratings = [1, 2, 5, 1]

Output

7

Explanation

The minimum we can pay for each respective programmer is [1, 2, 3, 1]```

### Solution :

```                        ```Solution in C++ :

vector<int> left(r.size(), 1), right(r.size(), 1);
for  (int i=1; i<r.size(); i++) {
if (r[i] > r[i-1]) left[i] = left[i-1] + 1;
}
for (int i=r.size()-2; i>=0; i--) {
if (r[i] > r[i+1]) right[i] = right[i+1] + 1;
}

int ans = 0;
for (int i=0; i<r.size(); i++) ans += max(left[i], right[i]);
return ans;```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public int solve(int[] ratings) {
if (ratings.length == 0)
return 0;
int[] left = new int[ratings.length];
int[] right = new int[ratings.length];
left[0] = 1;
for (int i = 1; i < ratings.length; i++) {
if (ratings[i] > ratings[i - 1]) {
left[i] = (1 + left[i - 1]);
} else
left[i] = 1;
}
right[ratings.length - 1] = 1;
for (int i = ratings.length - 2; i >= 0; i--) {
if (ratings[i] > ratings[i + 1]) {
right[i] = 1 + right[i + 1];
} else
right[i] = 1;
}
// System.out.println(Arrays.toString(left));
// System.out.println(Arrays.toString(right));
int[] pay = new int[ratings.length];
int cnt = 0;
for (int i = 0; i < ratings.length; i++) {
pay[i] = Math.max(left[i], right[i]);
cnt += pay[i];
}
return cnt;
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, ratings):
if not ratings:
return 0
n = len(ratings)
up = down = peak = 0
res = 1
for i in range(1, n):
if ratings[i - 1] < ratings[i]:
# going up case
up += 1
peak = up
down = 0
# 1 basic pay + up amount based on previous chain of increasing ratings
res += 1 + up
elif ratings[i - 1] == ratings[i]:
up = down = peak = 0
res += 1
else:
up = 0
down += 1
# down amount for chain of decreasing ratings + 1 basic pay if previous peak is smaller than current
res += down
if peak < down:
res += 1
return res```
```

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