Square Root without square root.

C
#include<stdio.h>

void main()
{
    int number;

    float temp, sqrt;

    printf("Provide the number: \n");

    scanf("%d", &number);

    // store the half of the given number e.g from 256 => 128
    sqrt = number / 2;
    temp = 0;

    // Iterate until sqrt is different of temp, that is updated on the loop
    while(sqrt != temp){
        // initially 0, is updated with the initial value of 128
        // (on second iteration = 65)
        // and so on
        temp = sqrt;

        // Then, replace values (256 / 128 + 128 ) / 2 = 65
        // (on second iteration 34.46923076923077)
        // and so on
        sqrt = ( number/temp + temp) / 2;
    }

    printf("The square root of '%d' is '%f'", number, sqrt);
}

Source

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