string npos in C++

npos: Value returned by various member functions when they fail.

Note: npos = 18446744073709551615ULL  (This is the value for npos in the strings of C++)

Syntax:

string::npos

For Example:

str = "abc"

str.find("d") => It returns npos value because d is not present in the string.

Approach

C++

#include <bits/stdc++.h>
using namespace std;

int main()
{
    string str = "abc";

    if (str.find("d") == string::npos)
        cout << "Not present";
    else
        cout << "Present\n";

    return 0;
}