C and C++ Programs

Passing Structures to Functions Here we can discuss passing structures and their members to functions . Passing Structure Members to Functions When you pass a member of a structure to a function , you are actually passing the value of that member to the function . Therefore, you are passing a simple variable (unless, of course, that element is compound, such as an array ). For example, consider this structure: struct fred { char x; int y; float z; char s[10]; } mike; Here are examples of each member being passed to a function: func(mike.x); /* passes character value of x */ func2(mike.y); /* ... Read Full Story

Structures A structure is a collection of variables referenced under one name, providing a convenient means of keeping related information together. A structure declaration forms a template that may be used to create structure objects (that is, instances of a structure). The variables that make up the structure are called members. (Structure members are also commonly referred to as elements or fields). Generally, all of the members of a structure are logically related. For example, the name and address information in a mailing list would normally be represented in a structure. The following code fragment shows how to declare a structure that defines the ... Read Full Story

Structure Assignments The information contained in one structure may be assigned to another structure of the same type using a single assignment statement. That is, you do not need to assign the value of each member separately. The following program illustrates structure assignments: #include int main(void) { struct { int a; int b; } x, y; x.a = 10; y = x; /* assign one structure to another */ printf(”%d”, y.a); return 0; } After the assignment, y.a will contain the value 10. Arrays of Structures Perhaps the most common usage of structures is in arrays of structures. To declare an array of structures, ... Read Full Story

I thought the following program was a perfect C program. But on compiling, I found a silly mistake. Can you find it out (without compiling the program :-) ? #include void OS_Solaris_print () { printf ( "Solaris - Sun Microsystems \n " ); } void OS_Windows_print () { printf ( "Windows - Microsoft \n " ); } void OS_HP-UX_print () { printf ( "HP-UX - Hewlett Packard \n " ); } int main () { int num ; printf ( "Enter the number (1-3): \n " ); scanf ( " %d " , & num ); switch ( num ) { case 1 : ... Read Full Story

Function Arguments If a function is to use arguments, it must declare variables that accept the values of the arguments. These variables are called the formal parameters of the function . They behave like other local variables inside the function and are created upon entry into the function and destroyed upon exit. As shown in the following function , the parameter declarations occur after the function name: /* Return 1 if c is part of string s; 0 otherwise. */ int is_in(char *s, char c) { while(*s) if(*s==c) return 1; else s++; return 0; } The function is_in() has two parameters: s and c ... Read Full Story