Skip to main content

Featured

C Program to Solve Two Sum Using Brute Force (With Algorithm & Output)

 Introduction The Two Sum problem is a popular coding interview question where we must find two indices of an array whose values add up to a given target. This program demonstrates a simple brute-force solution in C using nested loops and dynamic memory allocation. Problem Statement Given an integer array and a target value, return the indices of the two numbers such that they add up to the target. Each input has exactly one solution, and the same element cannot be used twice. The result should return the indices, not the values. If no solution exists, return NULL.  Algorithm / Logic Explanation Start the program. Traverse the array using a loop from index 0 to numsSize - 1 . Inside this loop, use another loop starting from i + 1 to numsSize - 1 . For every pair (i, j) , check if nums[i] + nums[j] == target . If condition becomes true: Allocate memory for 2 integers using malloc() . Store indices i and j . Set returnSize = 2 . Return the result poi...

Reverse a String in C

Reverse String in C

Reverse a String in C

This C program reverses a given string using a simple two-pointer technique. It swaps characters from both ends until the middle is reached.

✅ C Program Code:


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

void reverse(char str[])
{
    int start = 0;
    int end = strlen(str) - 1;
    int temp;
    while (start < end)
    {
        temp = str[start];
        str[start] = str[end];
        str[end] = temp;
        start++;
        end--;
    }
}

int main()
{
    char str[100];
    printf("Enter the string:\n");
    scanf("%[^\n]", str);
    printf("Before reversing the string: %s\n", str);
    reverse(str);
    printf("After reversing the string: %s", str);
}
  

๐Ÿ“Œ How It Works:

  • reverse(): Swaps characters from start and end using a while loop until the full string is reversed.
  • scanf("%[^\n]", str): Reads a line of input including spaces.
  • main(): Takes user input, prints original and reversed string.

๐Ÿ’ป Sample Output:

Enter the string:
Hello World
Before reversing the string: Hello World
After reversing the string: dlroW olleH

๐Ÿ” Keywords:

reverse string in C, string handling in C, two-pointer approach C, beginner string program, C logic examples, character array reverse

Comments

Popular Posts

๐ŸŒ™