# Make Target List with Increment and Double Operations - Amazon Top Interview Questions

### Problem Statement :

```You are given a list of non-negative integers target. Consider a list A of the same length as target containing all zeros initially. In one operation, you can increment one number in A, or double every number in A. Return the minimum number of operations required to turn A into target.

Constraints

0 ≤ n ≤ 100,000 where n is the length of target

Example 1

Input

target = [3, 2, 2]

Output

5

Explanation

We increment A[0] and get [1, 0, 0]
We increment A[1] and get [1, 1, 0]
We increment A[2] and get [1, 1, 1]
We double every element and get [2, 2, 2]
We increment A[0] and get [3, 2, 2]

Example 2

Input

target = [0, 0, 0, 0, 0]

Output

0

Explanation

A is already equal to target.```

### Solution :

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

int solve(vector<int>& target) {
map<int, int> c;
for (int x : target) ++c[x];
int ret = 0, b = 0;
for (const auto& p : c) {
int x = p.first, y = 0;
while (x) {
if (x % 2)
ret += p.second, --x;
else
x /= 2, ++y;
}
b = max(b, y);
}
return ret + b;
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, target):
max_len, cnt_ones = 0, 0
for n in target:
bits = bin(n)
max_len = max(max_len, len(bits) - 3)
cnt_ones += bits.count("1")
return max_len + cnt_ones```
```

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