Copy N Characters from One String to Another Without strncat()

C Program to Concatenate Two Strings Using a Pointer

Last Updated : 28 Nov, 2024

Concatenating two strings means appending one string at the end of another string. While the standard library provides strcat() for concatenation, this article will demonstrate how to concatenate two strings using pointers.

To concatenate two strings using pointers, traverse the first string to its null terminator and then start appending characters from the second string until its null terminator is reached.

C

#include <stdio.h>

void concat(char *s1, char *s2) {
  
    // Move pointer to the end of first string
    while (*s1) s1++;

    // Append each character of the second string
    while (*s2) {
        *s1 = *s2;
        s1++;
        s2++;
    }

    // Null-terminate the concatenated string
    *s1 = '\0';
}

int main() {
    char s1[100] = "Hello, ";
    char s2[] = "World!";

    // Call the concatenation function
    concat(s1, s2);

    printf("%s\n", s1);
    return 0;
}

Output

Hello Geeks

Explanation: The pointer s1 is incremented to move it to the end of the first string. Then characters from s2 are copied to the position pointed by s1. The pointer is incremented for both strings after each character is copied. After all characters from s2 are appended, a null terminator ('\0') is added at the end to complete the concatenated string.

Copy N Characters from One String to Another Without strncat()

R

rajpootveerendrasingh36

Improve

Article Tags :

Similar Reads

C Program to Compare Two Strings Using Pointers

In C, two strings are generally compared character by character in lexicographical order (alphabetical order). In this article, we will learn how to compare two strings using pointers. To compare two strings using pointers, increment the pointers to traverse through each character of the strings whi

C Program to Concatenate Two Strings Without Using strcat

String concatenation is the process of appending one string to the end of another. C language provides strcat() library function to concatenate string but in this article, we will learn how to concatenate two strings without using strcat() in C. The most straightforward method to concatenate two str

C Program to Print the Length of a String using Pointers

C language provides a built-in function strlen() but in this article, we will learn how to find and print the length of the string using pointers in C. The easiest method to find the length of a string using pointers is by calculating difference between the pointers to the first and last character o

C program to sort an array using pointers

Given an array of size n, the task is to sort this array using pointers in C. Examples: Input: n = 5, arr[] = {0, 23, 14, 12, 9} Output: {0, 9, 12, 14, 23} Input: n = 3, arr[] = {7, 0, 2} Output: {0, 2, 7} Approach: The array can be fetched with the help of pointers with the pointer variable pointin

C Program to Print the Length of a String Using %n Format Specifier

In C, strings are arrays of characters terminated by a null character ('\0') and the length of a string is the number of characters before this null character. In this article, we will learn how to find the length of the string using %n format specifier. The %n is a special format specifier for prin

C program to Compare Two Strings without using strcmp() function

String comparison refers to the process of comparing two strings to check if they are equal or determine their lexicographical order. C provides the strcmp() library function to compare two strings but in this article, we will learn how to compare two strings without using strcmp() function. The mos

Concatenating Two Strings in C

Concatenating two strings means appending one string at the end of another string. In this article, we will learn how to concatenate two strings in C. The most straightforward method to concatenate two strings is by using strcat() function. Let's take a look at an example: [GFGTABS] C #include <s

C Program to Create and Print Database of Students Using Structure

Prerequisites: Arrays in C/C++ Structure in C Using the structure pointer, we will implement a C program to create and print a database of students. In the below program, a structure student is created. The structure has five members: first_Name (string)last_Name (string)roll (integer)Branch(string)

C# Program To Reverse Words In A Given String

Example: Let the input string be "i like this program very much". The function should change the string to "much very program this like i" Examples: Input: s = "geeks quiz practice code" Output: s = "code practice quiz geeks" Input: s = "getting good at coding needs a lot of practice" Output: s = "p

C Program to Find the Length of a String

The length of a string is the number of characters in it without including the null character (â€˜\0â€™). In this article, we will learn how to find the length of a string in C. The easiest way to find the string length is by using strlen() function from the C strings library. Let's take a look at an ex