**Target Number with Operations - Google Top Interview Questions**

### Problem Statement :

Given positive integers start and end (start < end), return the minimum number of operations needed to convert start to end using these operations: Increment by 1 Multiply by 2 Constraints start < end < 2 ** 31 Example 1 Input start = 2 end = 9 Output 3 Explanation We can multiply 2 to get 4, and then again to get 8, then add 1 to get 9.

### Solution :

` ````
Solution in C++ :
int solve(int start, int end) {
int ops = 0;
for (; start * 2 <= end; ops++) {
if (end % 2)
end--;
else
end /= 2;
}
return ops + end - start;
}
```

` ````
Solution in Java :
class Solution {
public int solve(int start, int end) {
int ops = 0;
while (end / 2 >= start) {
ops += 1 + (end % 2);
end /= 2;
}
return ops + end - start;
}
}
```

` ````
Solution in Python :
class Solution:
def solve(self, start, end):
c = 0
if start <= 0:
return None
while end != start:
if end & 1: # Odd number
end -= 1
else:
res = end // 2
if res < start:
c += end - start
return c
end = res
c += 1
return c
```

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