HDU 1023 Train Problem II (卡特兰数)

Train Problem II

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 8450 Accepted Submission(s): 4525

Problem Description
As we all know the Train Problem I, the boss of the Ignatius Train Station want to know if all the trains come in strict-increasing order, how many orders that all the trains can get out of the railway.

Input
The input contains several test cases. Each test cases consists of a number N(1<=N<=100). The input is terminated by the end of file.

Output
For each test case, you should output how many ways that all the trains can get out of the railway.

Sample Input
1
2
3
10

Sample Output
1
2
5
16796

Hint

The result will be very large, so you may not process it by 32-bit integers.

Author
Ignatius.L

Recommend
We have carefully selected several similar problems for you: 1133 1130 1131 1134 2067

给出一个序列问有多少种出站顺序，符合卡特兰数的结构。用了kuangbin的板子。

#include "cstring"#include "cstdio"#include "iostream"#include "string.h"using namespace std;//*******************************//打表卡特兰数//第 n个 卡特兰数存在a[n]中，a[n][0]表示长度；//注意数是倒着存的，个位是 a[n][1] 输出时注意倒过来。//*********************************int a[105][100];void ktl(){    int i,j,yu,len;    a[2][0]=1;    a[2][1]=2;    a[1][0]=1;    a[1][1]=1;    len=1;    for(i=3;i<101;i++)    {        yu=0;        for(j=1;j<=len;j++)        {            int t=(a[i-1][j])*(4*i-2)+yu;            yu=t/10;            a[i][j]=t%10;        }        while(yu)        {            a[i][++len]=yu%10;            yu/=10;        }        for(j=len;j>=1;j--)        {            int t=a[i][j]+yu*10;            a[i][j]=t/(i+1);            yu = t%(i+1);        }        while(!a[i][len])        {            len--;        }        a[i][0]=len;    }}int main(){    ktl();    int n;    while(~scanf("%d",&n))    {        for(int i=a[n][0];i>0;i--)            printf("%d",a[n][i]);        printf("\n");    }}