1031. Hello World for U (20)

1. 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
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

关键在于计算n1，n2，n3

#include<iostream>#include<cstring>using namespace std;char str[100];int n1,n2,n3;void p(int n){    for (int i=0;i<n;i++)        cout<<" ";}int main(){    cin>>str;    int len=strlen(str);    int a,b;    n1=n3=(len+2)/3-1;    n2=len-n1-n3;    for ( a=0,b=len-1;a<n1&&b>n2;a++,b-- )    {       cout<<str[a];        p(n2-2);       cout<<str[b]<<endl;    }    for (int i=a;i<=b;i++)      cout<<str[i];    return 0;}