C++ programs to concatenate two string without using inbuilt functions

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Author: Sujith
Program: Write C++ programs to concatenate two string without using inbuilt functions
Prog Name: 1strcat.cpp
Date: 21-04-2015
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#include<iostream>
using namespace std;
void fnStrJoin(char s1[30],char s2[30]);
main()
{
    char str1[30],str2[30];
    system("clear");
    cout<<"Enter 1st string\n";
    cin>>str1;
    cout<<"Enter the second string\n";
    cin>>str2;
    fnStrJoin(str1,str2);
    cout<<"New String:"<<str1<<"\n";;
}
void fnStrJoin(char s1[30],char s2[30])
{
     int i,j=0;
     for(i=0;s1[i]!='\0';i++);
        while(s2[j]!='\0'){
            s1[i]=s2[j];
            i++;
            j++;
        }
s1[i]='\0';
}

OUTPUT:
"1strcat.cpp" 28L, 567C written
[141740@localhost ~]$ g++ 1strcat.cpp
[141740@localhost ~]$ ./a.out
Enter 1st string
Kerala
Enter the second string
Strikers
New String:KeralaStrikers
[141740@localhost ~]$