**Light Bulb Toggling - Amazon Top Interview Questions**

### Problem Statement :

You are given an integer n, and there's n switches in a room all in off position and n people who flip switches as follows: Person 1 comes and flips all switches that are multiples of 1, so all of them. Person 2 flips switches that are multiples of 2: 2, 4, 6, ... Person i flips switches that are multiples of i. Return number of switches that will be in on position at the end. Constraints 0 ≤ n < 2 ** 31 Example 1 Input n = 4 Output 2 Explanation Initially the bulbs are [0, 0, 0, 0] (not set). After player 1: [1, 1, 1, 1] After player 2: [1, 0, 1, 0] After player 3: [1, 0, 0, 0] After player 4: [1, 0, 0, 1] In the end there's 2 bulbs that are on and 2 that are off.

### Solution :

` ````
Solution in C++ :
int solve(int n) {
return sqrt(n);
}
```

` ````
Solution in Java :
import java.util.*;
class Solution {
public int solve(int n) {
int cnt = 0;
for (long i = 1; i * i <= n; i++) {
cnt++;
}
return cnt;
}
}
```

` ````
Solution in Python :
class Solution:
def solve(self, n):
return floor(math.sqrt(n))
```

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