CodeRunBox
Compiler
Glossary
Example
Course
Python
JavaScript
C
C++
Java
R
Kotlin
Introduction
C "Hello, World!" ProgramPrint an Integer (Entered by the User)Add Two IntegersMultiply Two Floating-Point NumbersFind ASCII Value of a CharacterCompute Quotient and RemainderFind the Size of int, float, double and charSwap Two Numbers
Decision Making and Loops
Check Whether a Number is Even or OddCheck Whether a Character is a Vowel or ConsonantFind the Largest Number Among Three NumbersFind the Roots of a Quadratic EquationCheck Leap YearCheck Whether a Number is Positive or NegativeCheck Whether a Character is an Alphabet or notCalculate the Sum of Natural NumbersFind Factorial of a NumberGenerate Multiplication TableDisplay Fibonacci SequenceFind GCD of two NumbersFind LCM of two NumbersDisplay Characters from A to Z Using LoopCount Number of Digits in an IntegerReverse a NumberCalculate the Power of a NumberCheck Whether a Number is Palindrome or NotCheck Whether a Number is Prime or NotDisplay Prime Numbers Between Two IntervalsCheck Armstrong NumberDisplay Armstrong Number Between Two IntervalsDisplay Factors of a NumberMake a Simple Calculator Using switch...casePrint Pyramids and Patterns
Functions
Demonstrate the Working of Keyword longDisplay Prime Numbers Between Intervals Using FunctionCheck Prime or Armstrong Number Using User-defined FunctionCheck Whether a Number can be Expressed as Sum of Two Prime NumbersFind the Sum of Natural Numbers using RecursionFind Factorial of a Number Using RecursionFind G.C.D Using RecursionConvert Binary Number to Decimal and vice-versaConvert Octal Number to Decimal and vice-versaConvert Binary Number to Octal and vice-versaReverse a Sentence Using Recursioncalculate the power using recursion
Arrays and Pointers
Calculate Average Using ArraysFind Largest Element in an ArrayCalculate Standard DeviationAdd Two Matrices Using Multi-dimensional ArraysMultiply Two Matrices Using Multi-dimensional ArraysFind Transpose of a MatrixMultiply two Matrices by Passing Matrix to a FunctionAccess Array Elements Using PointerC Program Swap Numbers in Cyclic Order Using Call by ReferenceFind Largest Number Using Dynamic Memory Allocation
Strings
Find the Frequency of Characters in a StringCount the Number of Vowels, Consonants and so onRemove all Characters in a String Except AlphabetsFind the Length of a StringConcatenate Two StringsCopy String Without Using strcpy()Sort Elements in Lexicographical Order (Dictionary Order)
Structures and Unions
Store Information of a Student Using StructureAdd Two Distances (in inch-feet system) using StructuresAdd Two Complex Numbers by Passing Structure to a FunctionCalculate Difference Between Two Time PeriodsStore Information of Students Using StructureStore Data in Structures Dynamically
File I/O
Write a Sentence to a FileRead the First Line From a FileDisplay its own Source Code as Output

C Program to Store Data in Structures Dynamically

To understand this example, you should have the knowledge of the following C programming topics:

This program asks the user to store the value of noOfRecords and allocates the memory for the noOfRecords structure variables dynamically using the malloc() function.

Demonstrate the Dynamic Memory Allocation for Structure


              

#include <stdio.h>
#include <stdlib.h>
struct course {
  int marks;
  char subject[30];
};

int main() {
  struct course *ptr;
  int noOfRecords;
  printf("Enter the number of records: ");
  scanf("%d", &noOfRecords);

  // Memory allocation for noOfRecords structures
  ptr = (struct course *)malloc(noOfRecords * sizeof(struct course));
  for (int i = 0; i < noOfRecords; ++i) {
    printf("Enter subject and marks:\n");
    scanf("%s %d", (ptr + i)->subject, &(ptr + i)->marks);
  }

  printf("Displaying Information:\n");
  for (int i = 0; i < noOfRecords; ++i) {
    printf("%s\t%d\n", (ptr + i)->subject, (ptr + i)->marks);
  }

  free(ptr);

  return 0;
}

Output


              

Enter the number of records: 2
Enter subject and marks:
Science 82
Enter subject and marks:
DSA 73

Displaying Information:
Science     82
DSA     73