#include<iostream>#include<string>#include<algorithm>#include <cstdio>#include <cstring>using namespace std;#define MAXN 9999#define DLEN 4class BigNum{private: int a[50]; //可以控制大数的位数 int len; //大数长度public: BigNum(){ len = 1; memset(a,0,sizeof(a)); } //构造函数 BigNum(const int); //将一个int类型的变量转化为大数 BigNum(const BigNum &); //拷贝构造函数 BigNum &operator=(const BigNum &); //重载赋值运算符，大数之间进行赋值运算 friend ostream& operator<<(ostream&, BigNum&); //重载输出运算符 BigNum operator+(const BigNum &) const; //重载加法运算符，两个大数之间的相加运算 BigNum operator*(const BigNum &) const; //重载乘法运算符，两个大数之间的相乘运算 bool operator>(const int & t)const; //大数和一个int类型的变量的大小比较 bool operator>(const BigNum & T)const; //大数和另一个大数的大小比较};BigNum dp[220][220];BigNum d(int x, int y) { if(x == y) return 1; if(x > y) return 1; if(dp[x][y] > 0) return dp[x][y]; if(y - x == 1) return (dp[x][y] = 1); BigNum ans = 0; for(int i = x+1; i <= y; i +=2) { ans = ans + d(x+1, i-1)*d(i+1, y); } return (dp[x][y] = ans);}int main(){ int n; while(scanf("%d", &n) == 1 && n != -1) { BigNum ans = d(1, 2*n); cout << ans << endl; } return 0;}BigNum::BigNum(const int b) //将一个int类型的变量转化为大数{ int c,d = b; len = 0; memset(a,0,sizeof(a)); while(d > MAXN) { c = d - (d / (MAXN + 1)) * (MAXN + 1); d = d / (MAXN + 1); a[len++] = c; } a[len++] = d;}BigNum::BigNum(const BigNum & T) : len(T.len) //拷贝构造函数{ int i; memset(a,0,sizeof(a)); for(i = 0 ; i < len ; i++) a[i] = T.a[i];}BigNum & BigNum::operator=(const BigNum & n) //重载赋值运算符，大数之间进行赋值运算{ int i; len = n.len; memset(a,0,sizeof(a)); for(i = 0 ; i < len ; i++) a[i] = n.a[i]; return *this;}ostream& operator<<(ostream& out, BigNum& b) //重载输出运算符{ int i; cout << b.a[b.len - 1]; for(i = b.len - 2 ; i >= 0 ; i--) { cout.width(DLEN); cout.fill('0'); cout << b.a[i]; } return out;}BigNum BigNum::operator+(const BigNum & T) const //两个大数之间的相加运算{ BigNum t(*this); int i,big; //位数 big = T.len > len ? T.len : len; for(i = 0 ; i < big ; i++) { t.a[i] +=T.a[i]; if(t.a[i] > MAXN) { t.a[i + 1]++; t.a[i] -=MAXN+1; } } if(t.a[big] != 0) t.len = big + 1; else t.len = big; return t;}BigNum BigNum::operator*(const BigNum & T) const //两个大数之间的相乘运算{ BigNum ret; int i,j,up; int temp,temp1; for(i = 0 ; i < len ; i++) { up = 0; for(j = 0 ; j < T.len ; j++) { temp = a[i] * T.a[j] + ret.a[i + j] + up; if(temp > MAXN) { temp1 = temp - temp / (MAXN + 1) * (MAXN + 1); up = temp / (MAXN + 1); ret.a[i + j] = temp1; } else { up = 0; ret.a[i + j] = temp; } } if(up != 0) ret.a[i + j] = up; } ret.len = i + j; while(ret.a[ret.len - 1] == 0 && ret.len > 1) ret.len--; return ret;}bool BigNum::operator >(const int & t) const //大数和一个int类型的变量的大小比较{ BigNum b(t); return *this>b;}bool BigNum::operator>(const BigNum & T) const //大数和另一个大数的大小比较{ int ln; if(len > T.len) return true; else if(len == T.len) { ln = len - 1; while(a[ln] == T.a[ln] && ln >= 0) ln--; if(ln >= 0 && a[ln] > T.a[ln]) return true; else return false; } else return false;}
