C Program to Print Hello World

In this article, you will learn and get code on printing Hello World in C programming. Hello World program is given here in following ways:

• Print Hello World using semicolon
• without using semicolon
• 10 times using for loop
• 10 times using while loop
• using string
• using user-defined function

Print Hello, World in C

This program simply prints Hello, World using printf() function. This function is defined in stdio.h header file.

#include<stdio.h>
#include<conio.h>
int main()
{
    printf("Hello, World");
    getch();
    return 0;
}

This program was build and run under Code::Blocks IDE. Here is its sample output:

Print Hello World without using Semicolon

To print Hello World without using semicolon (,), just put Hello World instead of Hello, World inside the printf() function as given in previous program. Rest of the things are same.

Print Hello World 10 Times using for Loop

Now let's create another program that uses for loop to execute the statement given below, 10 times:

printf("Hello World\n");

as shown in the program given below:

#include<stdio.h>
#include<conio.h>
int main()
{
    int i;
    for(i=0; i<10; i++)
        printf("Hello World\n");
    getch();
    return 0;
}

Here is its sample run:

The loop works in a way that:

• Initially (at very first run of for loop), 0 gets initialized to i and checks whether it is less than 10 or not
• The condition evaluates to be true, therefore program flow goes inside the loop and executes the statement
  printf("Hello World");
  that prints Hello World
• Now program flow goes to loop update part. There increments the value of i and again compares or checks the condition.
• After every updated value of i, program checks whether it is less than 10 or not
• If condition satisfies or evaluates to be true, then only program flow goes inside the loop. Otherwise program flow exits from the loop
• In this way, the Hello World gets printed on output screen 10 number of times

Print Hello World 10 Times using while Loop

Now instead of using for loop, this program uses while loop to do the same job as of previous program. To learn more about it (while loop), you can refer to its separate tutorial.

#include<stdio.h>
#include<conio.h>
int main()
{
    int i=0;
    while(i<10)
    {
        printf("Hello World\n");
        i++;
    }
    getch();
    return 0;
}

Produces the same output as of previous program.

Print Hello World using String

This program uses string to print Hello World. That is, a variable say str of type char gets declared and initialized with Hello World. And prints the value of str as output using %s format specifier.

#include<stdio.h>
#include<conio.h>
int main()
{
    char str[20] = "Hello World";
    printf("%s", str);
    getch();
    return 0;
}

Prints Hello World on output.

Print Hello World using Function

This is the last Hello World program which is created using a user-defined function printHello() that are being called from main() function. That is, we have declared the function before main() and defined it after main(). Now we are free to call it from main(). When it gets called, then its definition part gets executed, that prints Hello World on output.

#include<stdio.h>
#include<conio.h>
void printHello(void);
int main()
{
    printHello();
    getch();
    return 0;
}
void printHello(void)
{
    printf("Hello World");
}

also prints Hello World on output.

Same Program in Other Languages

• C++ Program to Print Hello World
• Java Program to Print Hello World
• Python Program to Print Hello World

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