Home »
C++ STL
std::string in C++ STL (Standard Template Library)
String in C++ STL (Standard Template Library): In this article, we are going to see how we can use string as a default datatype?
Submitted by Radib Kar, on February 27, 2019
String as datatype
In C, we know string basically a character array terminated by \0. Thus to operate with the string we define character array. But in C++, standard library gives us the facility to use string as a basic data type like integer.
Example:
Like we define and declare,
int i=5;
Same way, we can do for a string like,
String s= "IncludeHelp";
Remember, a string variable (literal) need to be defined under "". 'a' is a character whereas "a" is a string.
Basic operation that can be performed on string
Header file needed:
#include <string>
Or
#include <bits/stdc++.h>
C++ program to demonstrate example of std::string
#include <bits/stdc++.h>
using namespace std;
int main(){
string s;
//reading & printing
cout<<"Enter your string\n";
cin>>s;
cout<<"Sting you entered is: "<<s<<endl;
//printing size/length
cout<<"length of the "<<s<<" is = "<<s.length()<<endl;
//adding two strings
string s1="Include";
string s2="Help";
cout<<"s1+s2: "<<s1+s2<<endl;
//comparing
if(s1==s2)
cout<<s1<<" and "<<s2<<" are equal"<<endl;
else
cout<<s1<<" and "<<s2<<" are not equal"<<endl;
//accessing characters
cout<<"character at 0 index in "<<s<<" is = "<<s[0]<<endl;
cout<<"character at 1 index in "<<s<<" is = "<<s[1]<<endl;
cout<<"character at 5 index in "<<s<<" is = "<<s[5]<<endl;
return 0;
}
Output
Enter your string
IncludeHelp
Sting you entered is: IncludeHelp
length of the IncludeHelp is = 11
s1+s2: IncludeHelp
Include and Help are not equal
character at 0 index in IncludeHelp is = I
character at 1 index in IncludeHelp is = n
character at 5 index in IncludeHelp is = d