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 n₁ characters, then left to right along the bottom line with n₂ characters, and finally bottom-up along the vertical line with n₃ characters. And more, we would like U to be as squared as possible -- that is, it must be satisfied that n₁ = n₃ = max { k| k <= n₂ for all 3 <= n₂ <= N } with n₁ + n₂ + n₃ - 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

AC代码：

//本题比较简单，关键是求得n1和n2，注意输出格式即可

#include<stdio.h>
#include<string.h>

int main()
{
    //freopen("in.txt","r",stdin);
    int n1, n2;
	char s[81];
	while(scanf("%s",s)!=EOF) {
		int len = strlen(s);
		n1 = (len+2)/3; //由n1<=n2 && n1*2 +n2 = n分析可得
		n2 = len+2-2*n1;
		int i, j;
		for(i=0; i<n1-1; i++) { //前n1-1行，每行只输出第一列和最后一列元素，其余输出空格
			printf("%c",s[i]);
			for(j=0; j<n2-2; j++)
				printf(" ");
			printf("%c",s[len-1-i]);
			printf("\n");
		}
		for(i=n1-1; i<n1+n2-1; i++) //最后一行输出n2个数
			printf("%c",s[i]);
		printf("\n");
	}
    return 0;
}