How do I get a part of the a string in C++?

Question

How do I get a part of a string in C++? I want to know what are the elements from 0 to i.

Answer 1

You use substr, documented here:

#include 
#include 
using namespace std;
int main(void) {
    string a;
    cout << "Enter string (5 characters or more): ";
    cin >> a;
    if (a.size() < 5)
        cout << "Too short" << endl;
    else
        cout << "First 5 chars are [" << a.substr(0,5) << "]" << endl;
    return 0;
}

You can also then treat it as a C-style string (non-modifiable) by using c_str, documented here.