poj 1565 Skew Binary

#include <iostream>#include <string>using namespace std;string    st;void work(){    int        i, l = st.length(), temp = 1, ans = 0;    for (i = l - 1; i >= 0; i--)    {        temp *= 2;        ans += (st[i] - '0') * (temp - 1);    }    cout << ans << endl;}int main(){    while (getline(cin, st) && st != "0")        work();    return 0;}