#include <iostream>
#include <cmath>  // For pow function
 
int binaryToDecimal(const std::string& binary) {
    int decimal = 0;
    int length = binary.length();
 
    for (int i = 0; i < length; ++i) {
        if (binary[length - 1 - i] == '1') {
            decimal += std::pow(2, i);
        }
    }
    return decimal;
}
 
int main() {
    std::string binary = "1101";
    int decimal = binaryToDecimal(binary);
 
    std::cout << "Binary: " << binary << std::endl;
    std::cout << "Decimal: " << decimal << std::endl;
 
    return 0;
}
 

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