nested loops info help in c

[TeeWee]

i am trying to understand nested loops can someone explain to me how it works i don't under stand the concept this is the circle-drawing algorithm

for each row from 0 to diameter, inclusive
for each column from 0 to diameter, inclusive
distance = 4(row-radius)^2 + (column-radius)^2
distance = sqrt(distance)
if (distance > radius) print a space
otherwise print an *
print a newline to end the row

i don't understand for each row from the 0 to diameter part
or the for each column from 0 to diameter

the radius is user input to draw the circle.

also can someone tell me step by step also i need to understand this

#include<cstido>
#include <cmath>
int get();
void countdown(int radius);

int main()
{
int calc;
calc=get();
count(calc);
return 0;
}

int get()
{
//get user to enter number and print
//error message if not a number,-,or over 20
//this work fine
}

void countdown(int radius)
{
//this is the problem im having

int distance;
    for(int row=0; row<radius; row++){    //should i replace the radius? 
        for (int column =0; columne<radius; columne++){
        distance=4*pow(row-radius,2) + pow(columne-radius,2);   //this has distance
        distance=sqrt(distance);{                                         //this also distance maybe mistake?
             if (distance>radius){
                 printf(" ");
            }
            else{
                 printf("*");
             }
print("\n");
}
}
}

[SakurasouBusters]

Why are you using a function name (cout)?
I suggest you change the function to another name immediately.

[integralfx]

Make sure you properly indent your code, so it is easier to read.

#include<cstido>

void cout(int radius)

for (int column = 0; columne < radius; columne++)

print("*");

Typos.

distance = sqrt(distance) {

Unintended curly brace and missing semi-colon.

print(\n"); 

Typo and missing opening quotation mark

[TeeWee]

thank you.. i fix it.. by any chance do you know what for each row from 0 to diameter, inclusive
for each column from 0 to diameter, inclusive mean?

i just don't understand what it means by that.

the program suppose to make a * circle filled up filled with nested loops

the distance =sqrt(distance) should be sqrt*distance?