Algorithm-skew number

Algorithm-skew keyword one key word two

• topic
  • input
  • output
  • source
• full code

Title Description

In the skew binary representation, the value of the K-bit XK represents xk* (2^ (k+1)-1). The number of possible digits on each bit is 0 or 1, and the last face of a non 0 bit can be 2, for example, 10120 (skew) = 1* (2^5-1) + 0* (2^4-1) + 1* (2^3-1) + (2^2-1) + 0* (2^1-1) = 31 + 0 + 7 + 6 + 0 = 44. The first 10 skew numbers are 0, 1, 2, 10, 11, 12, 20, 100, 101, and 102.

Input

The input contains one or more rows, and each row contains an integer n. If n = 0 means the input ends, otherwise n is a skew number

Output

For each input, output its decimal representation. After conversion to decimal, n does not exceed 2^31-1 = 2147483647

Sample input

1012020000000000000000000000000000010100000000000000000000000000000011100111110000011100001011011020000

Sample output

44214748364632147483647471041110737

Source

http://bailian.openjudge.cn/practice/2973

Key points of the problem solving method

The topic is actually a conversion problem, which can be encapsulated into a function, and my approach is to use a string to save the input and then start the calculation from the last one to get the output. The function declaration is as follows:

int calc(char *num);

The implementation is as follows:

 int calc(char *num) {intsum =0;int Base=2;intn = strlen (num); for(inti = n; i >0; i--) {intA = num[i-1] -' 0 '; A *= (Base-1); sum + = A;Base*=2; }returnsum;}

Specific conversion ideas can refer to my other article algorithm-to determine the binary.

Full code

The problem is relatively simple, the complete code is as follows:

////Main.cpp//2973:skew number////Created by Limao on 15/6/11.//Copyright (c) 2015 Limao. All rights reserved.//#include <string.h>#include <stdio.h>#include <iostream>using namespace STD; int calc(char *num) {intsum =0;intBase =2;intn =strlen(num); for(inti = n; i >0; i--) {intA = num[i-1] -' 0 '; A *= (base-1);                sum + = A; Base *=2; }returnsum;} int main(int argc, const Char * argv[]) {Charnum[ *]; while(scanf('%s ', num) && num[0] !=' 0 '){//For Output        printf("%d\n", calc (num)); }return 0;}

Algorithm-skew number