1120 Friend Numbers （20 分)

最新推荐文章于 2021-02-26 12:55:12 发布

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最新推荐文章于 2021-02-26 12:55:12 发布

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本文提供了一道PAT甲级题目“1120FriendNumbers”的详细解答，介绍了如何通过计算整数各位数字之和来判断两个整数是否为“朋友数”，并分享了使用C++实现的代码示例。

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1120 Friend Numbers （20 分)

Two integers are called "friend numbers" if they share the same sum of their digits, and the sum is their "friend ID". For example, 123 and 51 are friend numbers since 1+2+3 = 5+1 = 6, and 6 is their friend ID. Given some numbers, you are supposed to count the number of different frind ID's among them.

Input Specification:

Each input file contains one test case. For each case, the first line gives a positive integer N. Then N positive integers are given in the next line, separated by spaces. All the numbers are less than 104.

Output Specification:

For each case, print in the first line the number of different frind ID's among the given integers. Then in the second line, output the friend ID's in increasing order. The numbers must be separated by exactly one space and there must be no extra space at the end of the line.

Sample Input:

8
123 899 51 998 27 33 36 12

Sample Output:

4
3 6 9 26

解题思路：暴风哭泣，PAT20分最简单的一道题吧没有弯弯绕绕

#include <iostream>
#include <bits/stdc++.h>
using namespace std;

set<int> s;

int culFriendId(int x)
{
    int sum = 0;
    while(x){
        sum += x%10;
        x/=10;
    }
    return sum;
}

int main()
{
    int n;
    scanf("%d",&n);
    for(int i = 0; i < n; i++){
        int x;
        scanf("%d",&x);
        s.insert(culFriendId(x));
    }
    cout << s.size() << endl;
    for(set<int>::iterator it = s.begin(); it != s.end(); it++){
        if(it!=s.begin()) printf(" ");
        printf("%d",*it);
    }
    return 0;
}