算法习题---5.8Unix ls命令（Uva400）

一：题目

输入正整数n以及n个文件名，将这n个文件名按照ASCII优先升序排列，按列优先方式左对齐输出。
注意：文件名最长的为M,那么最右列字符串长度为M,其他列的长度为M+2
注意：一列最多允许出现60个字符

（一）样例输入

10
tiny
2short4me
very_long_file_name
shorter
size-1
size2
size3
much_longer_name
12345678.123
mid_size_name
12
Weaser
Alfalfa
Stimey
Buckwheat
Porky
Joe
Darla
Cotton
Butch
Froggy
Mrs_Crabapple
P.D.
19
Mr._French
Jody
Buffy
Sissy
Keith
Danny
Lori
Chris
Shirley
Marsha
Jan
Cindy
Carol
Mike
Greg
Peter
Bobby
Alice
Ruben

（二）样例输出

------------------------------------------------------------
12345678.123         size-1             
2short4me            size2              
mid_size_name        size3              
much_longer_name     tiny               
shorter              very_long_file_name
------------------------------------------------------------
Alfalfa        Cotton         Joe            Porky        
Buckwheat      Darla          Mrs_Crabapple  Stimey       
Butch          Froggy         P.D.           Weaser       
------------------------------------------------------------
Alice       Chris       Jan         Marsha      Ruben     
Bobby       Cindy       Jody        Mike        Shirley   
Buffy       Danny       Keith       Mr._French  Sissy     
Carol       Greg        Lori        Peter                 

二：代码实现

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <string>
#include <algorithm>

#define MAX 100
#define MAX_COL 60

using namespace std;

void printStr(const string &str, int len, char ch)
{
    cout << str;
    for (int i = str.length(); i < len; i++)
        cout << ch;
}

int main()
{
    freopen("data5_8.in", "r", stdin);
    freopen("data5_8.out", "w", stdout);

    int num,max_len,rows,cols;
    string FileList[MAX];
    while (cin >> num)
    {
        max_len = 0;
        for (int i = 0; i < num; i++)
        {
            cin >> FileList[i];
            FileList[i].length() > max_len ? max_len = FileList[i].length() : max_len;
        }
        //计算行列
        cols = (MAX_COL - max_len) / (2 + max_len) + 1;
        rows = (num - 1) / cols + 1;
        //数据处理，进行排序
        sort(FileList, FileList + num);
        //进行数据输出
        printStr("", 60, '-');
        cout << endl;
        for (int r = 0; r < rows; r++)
        {
            for (int c = 0; c < cols; c++)
                printStr(FileList[rows*c + r], c == cols - 1 ? max_len : max_len + 2, ' ');
            cout << endl;
        }
    }

    freopen("CON", "r", stdin);
    freopen("CON", "w", stdout);
    return 0;
}