PAT-PAT (Advanced Level) Practise 1031. Hello World for U (20) (图形打印) 【二星级】
题目链接：http://www.patest.cn/contests/pat-a-practise/1031
题面：
1031. Hello World for U (20)
Given any string of N (>=5) characters, you are asked to form the characters into the shape of U. For example, "helloworld" can be printed as:
h d e l l r lowoThat is, the characters must be printed in the original order, starting top-down from the left vertical line with n 1 characters, then left to right along the bottom line with n 2 characters, and finally bottom-up along the vertical line with n 3 characters. And more, we would like U to be as squared as possible -- that is, it must be satisfied that n 1 = n 3 = max { k| k <= n 2 for all 3 <= n 2 <= N } with n 1 + n 2 + n 3 - 2 = N.
Input Specification:
Each input file contains one test case. Each case contains one string with no less than 5 and no more than 80 characters in a line. The string contains no white space.
Output Specification:
For each test case, print the input string in the shape of U as specified in the description.
Sample Input:helloworld!Sample Output:
h ! e d l l lowor
题目大意：
要求打印成u字形，且要让两边尽量长，但要小于等于底边长。
解题：
简单推导一下，可以发现，底边最多比两边长2，大于等于3的话，可以往两边挪。注意输出，推一下下标就好。
代码：
#include <cstdio>
#include <vector>
#include <iostream>
#include <string>
#include <algorithm>
using namespace std;
int main()
{
string s;
cin>>s;
int len=s.length(),a,b,c;
a=(len+2)/3;//两边长
b=(len+2)%3;//底边比两边长的长度
//数清楚个数，即可
for(int i=1;i<a;i++)
{
printf("%c",s[i-1]);
for(int j=0;j<(a+b-2);j++)
printf(" ");
printf("%c",s[len-i]);
printf("\n");
}
c=a-1;
//最后一行
for(int i=0;i<(a+b);i++)
printf("%c",s[c++]);
printf("\n");
return 0;
}