即卡特兰数。
#include <algorithm> #include <iostream> #include <cstring> #include <cstdio> #include <string> #include <stack> #include <cmath> #include <queue> #include <set> #include <map> #define FOR(i,s,t) for(int i = (s) ; i <= (t) ; ++i ) typedef long long ll; typedef unsigned long long ull; using namespace std; const int inf=0x3f3f3f3f; const int maxn=1e6+5; /* * 高精度,支持四则运算和小于比较。 */ struct BigInt { const static int mod = 10000; const static int DLEN = 4; const static int MAXN=9999; int a[600],len; BigInt() { memset(a,0,sizeof(a)); len = 1; } BigInt(int v) { memset(a,0,sizeof(a)); len = 0; do { a[len++] = v%mod; v /= mod; } while(v); } BigInt(const char s[]) { memset(a,0,sizeof(a)); int L = strlen(s); len = L/DLEN; if(L%DLEN)len++; int index = 0; for(int i = L-1; i >= 0; i -= DLEN) { int t = 0; int k = i - DLEN + 1; if(k < 0)k = 0; for(int j = k; j <= i; j++) t = t*10 + s[j] - ‘0‘; a[index++] = t; } } BigInt operator +(const BigInt &b)const { BigInt res; res.len = max(len,b.len); for(int i = 0; i <= res.len; i++) res.a[i] = 0; for(int i = 0; i < res.len; i++) { res.a[i] += ((i < len)?a[i]:0)+((i < b.len)?b.a[i]:0); res.a[i+1] += res.a[i]/mod; res.a[i] %= mod; } if(res.a[res.len] > 0)res.len++; return res; } BigInt operator -(const BigInt &b)const { int i,j,big; bool flag; BigInt t1,t2; if(b < *this) { t1=*this; t2=b; flag=0; } else { t1=b; t2=*this; flag=1; } big=t1.len; for(i=0; i<big; i++) { if(t1.a[i]<t2.a[i]) { j=i+1; while(t1.a[j]==0) j++; t1.a[j--]--; while(j>i) t1.a[j--]+=MAXN; t1.a[i]+=MAXN+1-t2.a[i]; } else t1.a[i]-=t2.a[i]; } t1.len=big; while(t1.a[len-1]==0 && t1.len>1) { t1.len--; big--; } if(flag) t1.a[big-1]=0-t1.a[big-1]; return t1; } BigInt operator *(const BigInt &b)const { BigInt res; for(int i = 0; i < len; i++) { int up = 0; for(int j = 0; j < b.len; j++) { int temp = a[i]*b.a[j] + res.a[i+j] + up; res.a[i+j] = temp%mod; up = temp/mod; } if(up != 0) res.a[i + b.len] = up; } res.len = len + b.len; while(res.a[res.len - 1] == 0 &&res.len > 1)res.len--; return res; } BigInt operator /(const int &b)const { BigInt res; int i,down=0; for(i=len-1; i>=0; --i) { res.a[i]=(a[i]+down*(MAXN+1) )/b; down=a[i]+down*(MAXN+1)-res.a[i]*b; } res.len=len; while(res.a[res.len-1]==0 && res.len>1)res.len--; return res; } bool operator <(const BigInt&b)const { int ln; if( len < b.len )return true; else if( len==b.len ) { ln=len-1; while(a[ln]==b.a[ln] && ln>=0 )ln--; if(ln>=0 && a[ln] < b.a[ln] )return true; else return false; } else return false; } void output() { printf("%d",a[len-1]); for(int i = len-2; i >=0 ; i--) printf("%04d",a[i]); printf("\n"); } }; BigInt a[110]; int main() { //freopen("in.txt","r",stdin); a[0]=BigInt(1); for(int i=1; i<=100; ++i) { a[i]=a[i-1]*( 4*i-2 )/(i+1); } int n; while(scanf("%d",&n)!=EOF) { if(n==-1)break; a[n].output(); } return 0; }
hdu1134 Game of Connections 高精度 四则运算 模板
原文:http://www.cnblogs.com/bruce27/p/4979152.html