UVA 1593 Alignment of Code（紫书习题5-1 字符串流）

You are working in a team that writes Incredibly Customizable Programming Codewriter (ICPC) which is basically a text editor with bells and whistles. You are working on a module that takes a piece of code containing some definitions or other tabular information and aligns each column on a fixed vertical position, while keeping the resulting code as short as possible, making sure that only whitespaces that are absolutely required stay in the code. So, that the first words on each line are printed at position p ₁ = 1; the second words on each line are printed at the minimal possible position p ₂, such that all first words end at or before position p₂ - 2; the third words on each line are printed at the minimal possible position p₃, such that all second words end at or before position p ₃ - 2, etc. 
For the purpose of this problem, the code consists of multiple lines. Each line consists of one or more words separated by spaces. Each word can contain uppercase and lowercase Latin letters, all ASCII punctuation marks, separators, and other non-whitespace ASCII characters (ASCII codes 33 to 126 inclusive). Whitespace consists of space characters (ASCII code 32).

Input

The input file contains one or more lines of the code up to the end of file. All lines (including the last one) are terminated by a standard end-of-line sequence in the file. Each line contains at least one word, each word is 1 to 80 characters long (inclusive). Words are separated by one or more spaces. Lines of the code can have both leading and trailing spaces. Each line in the input file is at most 180 characters long. There are at most 1000 lines in the input file.

Output

Write to the output file the reformatted, aligned code that consists of the same number of lines, with the same words in the same order, without trailing and leading spaces, separated by one or more spaces such that i-th word on each line starts at the same position p _i.

 

Sample Input

  start:  integer;    // begins here
stop: integer; //  ends here
 s:  string;
c:   char; // temp 

Sample Output

start: integer; // begins here
stop:  integer; // ends   here
s:     string;
c:     char;    // temp

关于代码对齐的练习   只需要找出每一列最长单词的长度，利用stringstream就可以轻松实现

vjudge 上的题目链接 ：https://cn.vjudge.net/problem/POJ-3959;
关键字： vector ， stringstream ， setw（） ,  string

 #include <iostream>
 #include <algorithm>
 #include <vector>
 #include <sstream>
 #include <iomanip>
 using namespace std;
 const int N =  + ;
 int max_len[];   //定义为全局列表 数组初始化为0
 //记录每一列最长的长度
 int main()
 {
     ios_base::sync_with_stdio(false);
     string line;
     int line_num = ;
     vector<string> tail[N];
     while(getline(cin,line)) //开始录入每一行的数据 遇到ctrl+z停止
     {
         int i=;
         string word;
         stringstream wordline(line); //word<<line  使用字符串流读取每一行的每一个单词
         while(wordline>>word)
         {
             max_len[i] = max(max_len[i],int(word.length()));
             tail[line_num].push_back(word);
             ++i;
         }
         ++line_num;
     }
     for(int i = ;i < line_num;i++)
     {
         for(int j = ;j < tail[i].size(); j++)
         {
             cout<<setiosflags(ios::left)<<setw(max_len[j]+)<<tail[i][j];
             //setiosflags(ios::left) 即控制向左输入
         }
         cout<<endl;
     }
     return ;
 }

tips: stringstream 很方便，，但也很慢。