Implement int sqrt(int x) function.

Calculate and return the square root of x, where x is a non-negative integer.

Since the return type is an integer, the result retains only the integer part, and the decimal part is dropped.

Example 1:
Input: 4
Output: 2

Example 2:
Input: 8
Output: 2
Instructions: The square root of 8 is 2.82842…
Since the return type is an integer, the decimal part will be omitted.

Next, I will explain my solution to this problem:

1. Determine the data type. Since the problem requires that the return type be an integer, the decimal part will be omitted, so I assign all values computed in the function to the integer type.
2. Determine the range of values to be calculated. It’s not hard to find that: $(\frac{x}{2} + 1)^2≥ x \\$(2x​+1)2≥x
   So, the maximum value of the root should not exceed $\frac{x}{2}$2x​.
3. We can consider a critical case: when the square of the value of the root is just above or equal to the value of x, the value of that root is returned.

Here is my code：

package main

import (
	"fmt"
)

func main() {
	var x int
	fmt.Scan(&x)
	var sqrt int
	sqrt=mySqrt(x)
	fmt.Println("Input:",x," Output:",sqrt)
	}
func mySqrt(x int) int {
	if(x<1){
		return x
	}
	start:=0
	end:=x/2+1
	var answer int
	for start=0;start<=end;start++ {
		if start*start==x {
			answer=start
		}else if start*start>x{
			answer=start-1
			break	//When start is greater than x, assign the value of start -1 to the answer
		}
	}
	return answer
}

Out put: