Why am I not getting the output from the program. Whenever I run my code it stop after taking the in-CodePudding

Here is my code I am expecting the output but I am not getting .It stop after taking the input I am expecting the output if i give name Harsh

Your name is Harsh

 #include <iostream>
 #include <cstring>
 using namespace std;
 
 int main() {
     cout << "Enter your name" << endl;
     char *s;
     cin >> s;
     cout << "Your name  is  " << s;
     return 0;
 }

I have also tried with cin.getline(s,100);but still it is not working. So I request to you to solve the problem and give me solution.

CodePudding user response：

Your code has undefined behavior because you are not allocating any memory for s to point at. s is an uninitialized pointer.

Try this instead:

#include <iostream>
using namespace std;

int main(){
    cout << "Enter your name" << endl;
    char s[100];
    cin >> s; // or: cin.getline(s,100);
    cout << "Your name is " << s;
    return 0;
}

Alternatively, you should use std::string instead, eg:

#include <iostream>
#include <string>
using namespace std;

int main(){
    cout << "Enter your name" << endl;
    string s;
    cin >> s; // or: getline(cin,s);
    cout << "Your name is " << s;
    return 0;
}

CodePudding user response：

s in your code is unallocated.

Since it is C we're talking about, you probably don't want to use pointers and memory allocation, and use std::string instead.

#include <iostream>
#include <string>
using namespace std;


int main ()
{
  cout << "Enter your name" << endl;
  string s;  // Instead of dealing with char* allocation and memory issues.
  cin >> s;
  cout << "Your name  is  " << s;
  return 0;
}

CodePudding user response：

you have done it correctly but the problem with output is because of the memory allocation. You have to allocate memory and try to avoid the concept of a pointer in that. Instead Use string s; or char s[50];