pku2084 Game of Connections

http://poj.org/problem?id=2084

组合数学，Catalan数，高精度

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

using namespace std;

const int ten[4] = {1, 10, 100, 1000};
const int max1=1000;

struct BigNumber{
    int d[max1];
    BigNumber(string s)
    {
        int len = s.size();
        d[0] = (len-1)/4+1;
        int i, j, k;
        for(i=1; i<max1; ++i) d[i] =0;
        for(i=len-1; i>=0; --i)
        {
            j = (len-i-1)/4+1;
            k = (len-i-1)%4;
            d[j]+=ten[k]*(s[i]-'0');
        }
        while(d[0]>1 && d[d[0]]==0) --d[0];
    }
    BigNumber()
    {
        *this = BigNumber(string("0"));
    }
    string toString()
    {
        string s("");
        int i, j, temp;
        for(i=3; i>=1; --i) if(d[d[0]]>=ten[i]) break;
        temp = d[d[0]];
        for(j=i; j>=0; --j)
        {
            s = s+(char)(temp/ten[j]+'0');
            temp %= ten[j];
        }
        for(i=d[0]-1; i>0; --i)
        {
            temp = d[i];
            for(j=3; j>=0; --j)
            {
                s = s+(char)(temp/ten[j]+'0');
                temp %= ten[j];
            }
        }
        return s;
    }
}zero("0"), d, temp, mid1[15];

BigNumber operator + (const BigNumber &a, const BigNumber &b){
    BigNumber c;
    c.d[0] = max(a.d[0], b.d[0]);
    int i, x=0;
    for(i=1; i<=c.d[0]; ++i)
    {
        x = a.d[i]+b.d[i] +x;
        c.d[i]=x%10000;
        x/=10000;
    }
    while(x!=0)
    {
        c.d[++c.d[0]] = x%10000;
        x/=10000;
    }
    return c;
}

BigNumber operator *(const BigNumber &a, const BigNumber &b){
    BigNumber c;
    c.d[0] = a.d[0] + b.d[0];
    int i, j, x;
    for(i=1; i<=a.d[0]; ++i)
    {
        x= 0;
        for(j=1; j<=b.d[0]; ++j)
        {
            x = a.d[i]*b.d[j]+x+c.d[i+j-1];
            c.d[i+j-1] = x%10000;
            x /= 10000;
        }
        c.d[i+b.d[0]] = x;
    }
    while((c.d[0]>1) && (c.d[c.d[0]]==0)) --c.d[0];
    return c;
}

int main()
{
    BigNumber one("1"), h[103];
    int i, j, n;
    h[0] = one;
    h[1] = one;
    for(n=2; n<=100; n++)
    {
        BigNumber sum("0");
        for(i=0; i<=n-1; i++)
        {
            sum = sum + (h[i] * h[n-i-1]);
        }
        h[n] = sum;
    }
    while(cin>>i, i+1)
    {
        cout<<h[i].toString()<<endl;
    }
    return 0;
}