Code:
#include <iostream>
#include <string>

using namespace std;

int main() {
    string info = "This is some info in a string!";

    string other = info.substr(5, 10); // substr(start, length)
    cout << other << endl;

    return 0;
}
You can synthesise Left and Right with intelligent use of substr.

PS: Get the length using .size()