public class Test {
public static void main(String[] args) throws Exception {
System.out.println(sevenToten("123456012"));
}
public static int sevenToten(String src) {
int num = 0;
char[] c = src.toCharArray();
for (int i=0; i<c.length; i++) {
num = (num << 3) - num;
num += (c[i]-'0');
}
return num;
}
}