图形输出题

问题

1031 Hello World for U (20 分)
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
lowo
That 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!
结尾无空行
Sample Output:
h !
e d
l l
lowor
结尾无空行

思路

字符串总长（N+2）/3即可求得左右两个竖直方向的字符数量。然后N+2减去竖直方向的字符数量剩下的就是底部的字符数量。

代码

#include <bits/stdc++.h>
using namespace std;
const int maxn = 85;
char str[maxn];
int main(){
    cin>>str;
    int len = strlen(str);
    int n1 = (len+2)/3,n3 = len+2 -(len+2)/3*2,i;
    for (i = 0; i < n1-1; ++i) {
        cout<<str[i];
        for (int k = 0; k < n3 - 2; ++k) {
            cout<<" ";
        }
        cout<<str[len-1-i];
        if(i!=n1-1)
            cout<<endl;
    }
    for (int k = i; k < n1+n3-1; ++k) {
        cout<<str[k];
    }
    cout<<endl;
    return 0;
}

总结

注意字符的输出顺序是蛇形的。