COJ 1102 - You Can Say 11 题解

本题就是给出一个无穷大数，算其能否被11除尽

Description

Your job is, given a positive number N, determine if it is a multiple of eleven.

Input specification

The input is a file such that each line contains a positive number. A line containing the number 0 is the end of the input. The given numbers can contain up to 1000 digits.

Output specification

The output of the program shall indicate, for each input number, if it is a multiple of eleven or not.

Sample input

112233
30800
2937
323455693
5038297
112234
0

Sample output

112233 is a multiple of 11.
30800 is a multiple of 11.
2937 is a multiple of 11.
323455693 is a multiple of 11.
5038297 is a multiple of 11.
112234 is not a multiple of 11.

使用string模拟除法就能够了。

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
using namespace std;

bool divEleven(string s)
{
	int carry = 0;
	for (int i = 0; i < s.size(); i++)
	{
		int d = carry * 10 + s[i] - '0';
		carry = d % 11;
	}
	if (carry) return false;
	return true;
}

void Eleven()
{
	string S;
	while (cin>>S && "0" != S)
	{
		if (divEleven(S)) cout<<S<<" is a multiple of 11.\n";
		else cout<<S<<" is not a multiple of 11.\n";
	}
}