Question

How to check if a string contains only 0 and 1 in C++

Answer 1

#include <iostream>
#include <string>

bool isBinary(const std::string& s) {
    return s.find_first_not_of("01") == std::string::npos;
}

int main() {
    std::string s = "1010011";

    isBinary(s) ? std::cout << "Valid string\n" : std::cout << "Invalid string\n";
    isBinary("0000") ? std::cout << "Valid string\n" : std::cout << "Invalid string\n";
    isBinary("1111") ? std::cout << "Valid string\n" : std::cout << "Invalid string\n";
    isBinary("1021") ? std::cout << "Valid string\n" : std::cout << "Invalid string\n";
}



/*
run:

Valid string
Valid string
Valid string
Invalid string

*/

 

70+ SQL courses for beginners and professionals