C programming examples

C program to find hcf and lcm: The code below finds highest common factor and least common multiple of two integers. HCF is also known as greatest common divisor(GCD) or greatest common factor(gcf).

C programming code

#include <stdio.h>
 
int main() {
  int a, b, x, y, t, gcd, lcm;
 
  printf("Enter two integers\n");
  scanf("%d%d", &x, &y);
 
  a = x;
  b = y;
 
  while (b != 0) {
    t = b;
    b = a % b;
    a = t;
  }
 
  gcd = a;
  lcm = (x*y)/gcd;
 
  printf("Greatest common divisor of %d and %d = %d\n", x, y, gcd);

C program to merge two arrays into third array: Arrays are assumed to be sorted in ascending order. You enter two short sorted arrays and combine them to get a large array.

C programming code to merge two sorted arrays

#include <stdio.h>
 
void merge(int [], int, int [], int, int []);
 
int main() {
  int a[100], b[100], m, n, c, sorted[200];
 
  printf("Input number of elements in first array\n");
  scanf("%d", &m);
 
  printf("Input %d integers\n", m);
  for (c = 0; c < m; c++) {
    scanf("%d", &a[c]);
  }

assert is a macro which is useful to check certain conditions at run time(when the program is under execution) and is very useful while debugging a program. To use it you must include the header file "assert.h" in your program.

Declaration: void assert(int expression);

Expression is any valid c language expression, mostly it's a condition. In the example we divide two integers or calculate a/b and you know that b can't be zero so we use

C programming code to reverse words in a string or sentence, For example if the input string is "c++ programming language" then the output will be "++c gnimmargorp egaugnal" i.e. we will invert each word occurring of the input string. Algorithm is very simple just scan the string and keep on storing characters until a space comes. If a space is found then we have found one word so we append null terminator and then reverse the word and then copy the characters of original string with the string obtained on reversing. Then repeat the previous step until the string ends.

C program to print first n natural numbers without using any loop(do while, for or while). In the first program we will use recursion to achieve the desired output and in the second we use goto statement i.e. without creating any function other than main.

C programming code using recursion

#include <stdio.h>
 
void print(int);
 
int main()
{
  int n;
 
  scanf("%d", &n);
 
  print(n);
 
  return 0;
}
 
void print(int n)
{
  static int c = 1;
 
  if (c == n+1)
    return;
 
  printf("%d\n", c);
  c++;
  print(n);
}