C program to Concatenate Two Strings without using strcat()

C program to Concatenate Two Strings Using While Loop

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

int main()
{
    clrscr();
    char Str1[100], Str2[100];
    int i, j;

    printf("\n Please Enter the First String :  ");
    gets(Str1);

    printf("\n Please Enter the Second String :  ");
    gets(Str2);

    i = 0;
    while( Str1[i]!='\0')
    {
        i++;
    }

    j = 0;
    while( Str2[j]!='\0')
    {
        Str1[i] = Str2[j];
        i++;
        j++;
    }
    Str1[i] = '\0';

    printf("\n String after the Concatenate = %s", Str1);

    return 0;
    getch();
 }
 

C program to Concatenate Two Strings Using Functions

#include<stdio.h>
#include<conio.h>
#include<string.h>
void concatenate(char [], char []);
int main()
{
    clrscr();
    char Str1[100], Str2[100];

    printf("\n Please Enter the First String :  ");
    gets(Str1);

    printf("\n Please Enter the Second String :  ");
    gets(Str2);
    concatenate(Str1, Str2);

    printf("\n String after the Concatenate = %s", Str1);

    return 0;
}
  void concatenate(char s1[], char s2[])
{
    int i, j;
    i = 0;
    while( s1[i]!='\0')
    {
        i++;
    }

    j = 0;
    while( s2[j]!='\0')
    {
        s1[i] = s2[j];
          i++;
        j++;
      }
    s1[i] = '\0';

 }
 

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