Online C Programming Test - C Programming Test - Random

Declaration: char *strrchr(const char *s, int c);

It scans a string s in the reverse direction, looking for a specific character c.

Example:

#include <string.h>
#include <stdio.h>

int main(void)
{
   char text[] = "I learn through IndiaBIX.com";
   char *ptr, c = 'i';

   ptr = strrchr(text, c);
   if (ptr)
      printf("The position of '%c' is: %d\n", c, ptr-text);
   else
      printf("The character was not found\n");
   return 0;
}

Output:

The position of 'i' is: 19

i = printf("How r u\n"); This line prints "How r u" with a new line character and returns the length of string printed then assign it to variable i.
So i = 8 (length of '\n' is 1).

i = printf("%d\n", i); In the previous step the value of i is 8. So it prints "8" with a new line character and returns the length of string printed then assign it to variable i. So i = 2 (length of '\n' is 1).

printf("%d\n", i); In the previous step the value of i is 2. So it prints "2".

A function cannot be defined inside the another function, but a function can be called inside a another function.

Step 1: int check(int); This prototype tells the compiler that the function check() accepts one integer parameter and returns an integer value.

Step 2: int l=45, c; The variable i and c are declared as an integer type and i is initialized to 45.

The function check(i) return 100 if the given value of variable i is >=(greater than or equal to) 45, else it will return 10.

Step 3: c = check(i); becomes c = check(45); The function check() return 100 and it get stored in the variable c.(c = 100)

Step 4: printf("%d\n", c); It prints the value of variable c.

Hence the output of the program is '100'.

fmod(x,y) - Calculates x modulo y, the remainder of x/y.
This function is the same as the modulus operator. But fmod() performs floating point or long double divisions.

Step 1: int i = 0; here variable i is declared as an integer type and initialized to '0'(zero).
Step 2: i++; here variable i is increemented by 1(one). Hence, i = 1
Step 3: if(i <= 5) becomes if(1 <= 5) here we are checking '1' is less than or equal to '5'. Hence the if condition is satisfied.
Step 4: printf("IndiaBIX\n"); It prints "IndiaBIX"
Step 5: exit(); terminates the program execution.

Hence the output is "IndiaBIX".

A call stack or function stack is used for several related purposes, but the main reason for having one is to keep track of the point to which each active subroutine should return control when it finishes executing.

A stack overflow occurs when too much memory is used on the call stack.

Here function main() is called repeatedly and its return address is stored in the stack. After stack memory is full. It shows stack overflow error.

The compiler will not know that the function int fun() exists. So we have to define the function prototype of int fun();
To overcome this error, see the below program

#include<stdio.h>
int fun(); /* function prototype */

int main()
{
    int (*p)() = fun;
    (*p)();
    return 0;
}
int fun()
{
    printf("IndiaBix.com\n");
    return 0;
}

If the index of the array size is exceeded, the program will crash. Hence "option c" is the correct answer. But the modern compilers will take care of this kind of errors.

Example: Run the below program, it will crash in Windows (TurboC Compiler)

#include<stdio.h>

int main()
{
    int arr[2];
    arr[3]=10;
    printf("%d",arr[3]);
    return 0;
}

Since C is a compiler dependent language, it may give different outputs at different platforms. We have given the Turbo-C Compiler (Windows) output.

Please try the above programs in Windows (Turbo-C Compiler) and Linux (GCC Compiler), you will understand the difference better.

Step 1:

printf("%d, %d, %d", sizeof(3.0f), sizeof('3'), sizeof(3.0));

The sizeof function returns the size of the given expression.

sizeof(3.0f) is a floating point constant. The size of float is 4 bytes

sizeof('3') It converts '3' in to ASCII value.. The size of int is 2 bytes

sizeof(3.0) is a double constant. The size of double is 8 bytes

Hence the output of the program is 4,2,8

Note: The above program may produce different output in other platform due to the platform dependency of C compiler.

In Turbo C, 4 2 8. But in GCC, the output will be 4 4 8.