Chapter 1. Basic C and Algorithm

Let look at this code snipset 

#include <stdio.h>

int main(void)
{
    int a , b , c;

    int max;
    printf("Getting a max value of 3");
    printf("a: "); scanf("%d", &a);
    printf("b: "); scanf("%d", &b);
    printf("c: "); scanf("%d", &c);

    max = a;

    if(b > max) max = b;
    if(c > max) max = c;

    prinft("Max value is %d", max);

    return 0;
    
    
}

scanf need to use & (Ampersand) .. Lets not go super deep at this point but..!

Lets think scanf need to get variable address by & and dump value to the address.

 

Just remember at this point '&' gets the address value of the variable.

 

This code shows super basic algorithm.

 

1. put max value in a

2. If b is bigger than max put b in max

3. If c is bigger than max put c in max

 

This is called concatenation structure / algorithm that is runs in order (top to bottom)

So we can think Algorithm as a just bunch of if and looping statement.

 

Next example is a basic looping code

    int i, n;
    int sum;
    printf("Print 1 - n");
    scanf("%d", &n);
    sum = 0;

    for (int i = 0; i < n; i++)
    {
        sum += i;
    }

    prinf("Sum of 1 to n i s %d");

 

The loop statement loops till when i reach to n.

 

So we can think Algorithm as mixing the if and loop statement to get the answer ( and some recursion .. which I hate).