[Introduction to Programming-c] numbers for eigenvalues

The topic is the exercises of the C language of NetEase cloud classroom

Topic content:

It is a common coding algorithm to find the eigenvalues of numbers, and the odd-even feature is a simple characteristic value. For an integer, each digit is numbered from bit to digit, number 1th, 10 digit is 2nd, and so on. This integer number on the nth bit is recorded as x, if the parity of X and N is the same, write down a 1, otherwise write down a 0. 0 and 1 of the parity of the corresponding bit are recorded in the order of integers, and a binary number is formed. For example, for 342315, this binary number is 001101.

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By adding the bit value of 1 bits to the bits value, you get the result 13.

Your program reads a nonnegative integer, the range of integers is [0,100000], and then calculates the binary number that represents the parity by the above algorithm, outputting its corresponding decimal value.

Tip: The integer is decomposed from right to left, the digits are added 1 at a time, and the binary value is multiplied by 2.

Input format:

A nonnegative integer in which the range of integers is [0,100000].

Output format:

An integer that represents the result of the calculation.

Input Sample:

342315

Sample output:

13

My solution: The main use of bit operations to judge parity, XOR or to determine whether the consistency

#include <stdio.h>int main () {int in,out,pos;out = pos = 0;//init scanf ("%d", &in), while (in > 0) {int flag = (( IN%10) (&1) ^ (pos&1);//Whether the value is consistent based on the number parity and the digital parity. Since the POS is calculated from 0, so with XOR, just achieve odd parity parity get 1 rule out + = flag<<pos;// The left shift number turns into 10 binary note instead of right shift pos++;in/= 10;} printf ("%d", out); return 0;}

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[Introduction to Programming-c] numbers for eigenvalues