Skip to main content

Hello World C Program with full explanation.

Hello World C Program with Explanation are given below :-

#include<stdio.h>
#include<conio.h>
void main()
{
clrscr();
printf("Hello World!");
getch();
}

Explanations:-
printf() function is defined in the header file stdio.h, so it must be included at top of the program. Like clrscr() and getch() functions are defined in conio.h.
To include a Header file, the syntax is #include at the top of the program.
C Program to be written in main() function. Then void main() means the main() function returns nothing and it will study later.
We use ";" as a statement terminator so clrscr(),printf() and getch() are used ";" but "void main()" doesn't have ";" because it is not terminated there, it follows "{" and "}" .
clrscr() function uses for to clear the screen.
printf() for print something.
getch() uses for to get a character from keyboard and it is used here as a wait command.
Save file name as "anyname.c"
Compile using Alt+F9
Run using Ctrl+F9
The output will be as:

Hello World!

then press enter key to return to the source program editor.

Popular posts from this blog

Swapping of Two Numbers in C or C Program to Swap Two Numbers

Swapping of Two Numbers in C or C Program to Swap Two Numbers or C program to Swap two numbers without using a third variable #include <stdio.h> #include <conio.h>  void main() {    int x, y, temp;    clrscr();    // to clear screen       printf("Enter the value of x and y\n");    scanf("%d%d", &x, &y);    printf("Before Swapping\nx = %d\ny = %d\n",x,y);    temp = x;    x    = y;    y    = temp;    /*       without using temp variable, this can be used    let x=4 and y=5    x = x + y ;   x=x+y => x=4+5 => x=9     y = x - y ;   y=x-y => y=9-5 => y=4  value changed    x = x - y ;   x=x-y => x=9-4 => x=5  value changed      */       printf("After Swapping\nx ...

Find the Greatest Time in C or CPP from two different times.

Find the Greatest Time in C or CPP from two different times. Example Code: #include<iostream.h> #include<conio.h> class time { private: int hh,mm,ss; public: void get() { cout<<"\n enter hh,mm,ss:"; cin>>hh>>mm>>ss; } void show() { cout<<"\n hour:"<<hh<<"\n minute:"<<mm<<"\n second:"<<ss; } time greatest(time x) { if (hh>x.ss) return *this; else if(hh>x.hh) return x; else if(mm>x.mm) return *this; else if(mm<x.mm) return x; else if(ss>x.ss) return *this; else return x; } }; void main() { clrscr(); time t1,t2,t3; cout<<"\n enter time1:"; t1.get(); cout<<"\n enter time2:"; t2.get(); t3=t1.greatest(t2); cout<<"\n greatest time:"; t3.show(); getch(); }

How to Compile and Run CGI Scripts in C Examples in Linux Apache Server

How to Compile and Run CGI Scripts in C Examples in Linux Apache Server :- first let us create an HTML file(testcgi.html) : it can be made using keditor, geditor or vi editor Enter First Number : Enter Second Number : use form action http://localhost/cgi-bin/sum.cgi then we have to make a C Program (sum.c): #include<stdio.h> #include<stdlib.h> int main(void) { char *data; long m,n; printf("%s%c%c\n","Content-Type:text/html;charset=iso-8859-1",13,10); printf(" Result \n"); printf(" HTML Form values are added... \n"); data = getenv("QUERY_STRING"); if(data == NULL) printf("Error! Error in passing data from form to script."); else if(sscanf(data,"m=%ld&n=%ld",&m,&n)!=2) printf("Error! Invalid data. Data must be numeric."); else printf("The Sum of %ld and %ld is %ld.",m,n,m+n); return 0; } To Compile: in linux login root user and go to command line terminal root# cc sum.c...