#include <bits/stdc++.h>
using namespace std;
int main()
{
    //char s1[100], s2[100], i, j;
	string s1("hello");
	string s2="world";
	s1=s1+s2;
    //printf("Enter first string: ");
    //scanf("%s", s1);
 
   // printf("Enter second string: ");
    //scanf("%s", s2);
 
    // calculate the length of string s1
    // and store it in i
 /*   for(i = 0; s1[i] != '\0'; ++i);
 
    for(j = 0; s2[j] != '\0'; ++j, ++i)
    {
        s1[i] = s2[j];
    }
 
    s1[i] = '\0';*/
    //s1=s1+s2;
    cout<<s1<<"\n";
    printf("After concatenation: %s", s1);
 
    return 0;
}

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