#include <iostream>
int BinDec(char* bin)
{
    int rez = 0, i, size = strlen(bin);
    for(i = size - 1; i >= 0; --i)
        rez += ((int)bin[i] - 48)<<i;
    return rez;
}
int main()
{
    char ch[] = "1111";
    std::cout<<BinDec(ch);
}

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