Skip to main content

Scope : Local And Global

From the computer’s point of view, a C program is nothing more than
a collection of functions and declarations.

Functions can be thought of as sealed capsules of program code which float on a background of white space,and are connected together by means of function calls. White space is the name given to the white of an imaginary piece of paper upon which a program is written, in other words the spaces and new line characters which are invisible to the eye. The global white space is only the gaps between functions, not the gaps inside functions. Thinking of functions as sealed capsules is a useful way of understanding the difference between local and global objects and the whole idea of scope in a program.


Another analogy is to think of what goes on in a function as being like

watching a reality on television. You cannot go in and change the TV reality,only observe the output, but the television show draws its information fromthe world around it. You can send a parameter (e.g. switch channels) tomake some choices. A function called by a function, is like seeing someonewatching a televsion, in a television show.
Labels:

Popular posts from this blog

C++ Program to find the sum, difference, product and quotient of two integers

#include <iostream.h> #include <conio.h> void main() {   clrscr();   int x = 10;   int y = 2;   int sum, difference, product, quotient;   sum = x + y;   difference = x - y;   product = x * y;   quotient = x / y;   cout << "The sum of " << x << " & " << y << " is " << sum << "." << endl;   cout << "The difference of " << x << " & " << "y <<  is " << difference << "." << endl;   cout << "The product of " << x << " & " << y << " is " << product << "." << endl;   cout << "The quotient of " << x << " & " << y << " is " << quotient << "." << endl;   getch(); }
Read more

Program of virtual piano

//////////////Tested And Created By C++/////////////////////////////// #include<stdio.h> #include<dos.h> #include<conio.h> #include<stdlib.h> #define SHOW 1 #define HIDE 2 union REGS input,output; class piano {  public:int BIGKEY,MIDKEY,back,border;     piano()//init constructor     {         BIGKEY=15;         MIDKEY=1;         back=7;         border=15;     } }color; void drawpiano(int x,int y); int check_xy(int x,int y); void BOX(int c,int r,int c1,int r1,int col); int initmouse(); void setupscreen(); void pointer(int on); void restrictmouse(int x1,int y1,int x2,int y2); void check_keys(int x,int y); void getmouse(int *button,int *x,int *y); float freq[7] = {130.81, 146.83, 164.81, 174.61,196, 220, 246.94 } ; int n=0,a=4,backcolor=2,exitcode=1; void showbar(int t) {  if(t>65) t=65;  if(t<1) t=1;  textcolor(15);  for(int q=0;q<=t;t++)  {     gotoxy(3+q,4);     cprintf("Û");  } } void main() {  int
Read more

Putimage function in c

putimage function outputs a bit image onto the screen. Declaration:- void putimage(int left, int top, void *ptr, int op); putimage puts the bit image previously saved with getimage back onto the screen, with the upper left corner of the image placed at (left, top). ptr points to the area in memory where the source image is stored. The op argument specifies a operator that controls how the color for each destination pixel on screen is computed, based on pixel already on screen and the corresponding source pixel in memory. c smiling face animation This animation using c draws a smiling face which appears at random position on screen. See output below the code, it will help you in understanding the code easily. C programming code #include<graphics.h> #include<conio.h> #include<stdlib.h>   main() { int gd = DETECT, gm, area, temp1, temp2, left = 25, top = 75; void *p;   initgraph(&gd,&gm,"C:\\TC\\BGI");   setcolor(YELLOW);
Read more