Binary

Intro

Decimal is a base-10 system.

A number 23 in base 10 notation can be understood as a linear combination of powers of 10:

• The rightmost digit gets multiplied by 10^0 = 1
• The next number gets multiplied by 10^1 = 10
• ...
• The n*th number gets multiplied by 10^(n-1)*.
• All these values are summed.

So: 23 => 2*10^1 + 3*10^0 => 2*10 + 3*1 = 23 base 10

Binary is similar, but uses powers of 2 rather than powers of 10.

So: 101 => 1*2^2 + 0*2^1 + 1*2^0 => 1*4 + 0*2 + 1*1 => 4 + 1 => 5 base 10.

Task

Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles.

Implement binary to decimal conversion. Given a binary input string, your program should produce a decimal output. The program should handle invalid inputs.

Note

• Implement the conversion yourself. Do not use something else to perform the conversion for you.

The Code

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#include "binary.h"
#include <cctype>
#include <cstdint>

namespace binary {
std::uint32_t convert(std::string test) {
std::uint32_t result{};
for (auto c : test) {
    if (std::isdigit(c)) {
    result <<= 1;
    if (c == '1') {
        result |= 1;
    }
    } else
    return 0;
}
return result;
}
} // namespace binary

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#include <bits/stdint-uintn.h>
#include <cstdint>
#include <string>
#if !defined(BINARY_H)
#define BINARY_H
#include "string"
namespace binary {
    std::uint32_t convert(std::string);
}  // namespace binary

#endif // BINARY_H

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