高精：
#include<bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN=100000,B=100000000,MAXM=3000;
int A[MAXN+5];
namespace Huge_int {
using namespace std;
struct huge_int {
int n;
int a[MAXM+5];
inline void clear() { memset(a,0,sizeof(a));n=0; }
inline void work() { while(n>1 && !a[n]) n--; }
inline huge_int rd() {
memset(A,0,sizeof(A));
clear();
char ch=getchar();
while(ch<'0' || ch>'9') ch=getchar();
while(ch<='9' && ch>='0') A[++n]=ch-'0',ch=getchar();
for(int i=1;i+i<=n;++i) swap(A[i],A[n-i+1]);
for(int i=1;i<=n;i+=8){
int j=(i+7)/8;
a[j]=(A[i]+A[i+1]*10+A[i+2]*100+A[i+3]*1000+A[i+4]*10000+A[i+5]*100000+A[i+6]*1000000+A[i+7]*10000000);
}
n=(n+7)/8;
return *this;
}
inline huge_int wrt() const {
printf("%lld",a[n]);
for(int i=n-1;i>=1;--i) printf("%08lld",a[i]);
putchar('\n');
return *this;
}
inline bool operator < (const huge_int &nt) const {
if(n<nt.n) return 1;
if(n>nt.n) return 0;
for(int i=n;i>=1;--i)
if(a[i]!=nt.a[i])return a[i]<nt.a[i];
return 0;
}
inline bool operator > (const huge_int &nt) const {
return nt<*this;
}
inline bool operator != (const huge_int &nt) const {
return (*this<nt) || (nt<*this);
}
inline bool operator == (const huge_int &nt) const {
return !(*this!=nt);
}
inline huge_int operator = (const int &nt) {
n=0;
int x=nt;
while(x){
a[++n]=x%B;
x/=B;
}
return *this;
}
inline huge_int operator + (const huge_int &nt) const {
huge_int tmp;
tmp.clear();
tmp.n=max(n,nt.n)+1;
for(int i=1;i<=tmp.n;++i){
tmp.a[i]+=a[i]+nt.a[i];
tmp.a[i+1]+=tmp.a[i]/B;
tmp.a[i]%=B;
}
tmp.work();
return tmp;
}
inline huge_int operator - (const huge_int &nt) const {
huge_int tmp;
tmp.clear();
int x=0;
tmp.n=n;
for(int i=1;i<=tmp.n;++i){
x+=a[i]-nt.a[i];
if(x<0) tmp.a[i]=x+B,x=-1;
else tmp.a[i]=x,x=0;
}
tmp.work();
return tmp;
}
inline huge_int operator * (const huge_int &nt) const {
huge_int tmp;
tmp.clear();
tmp.n=n+nt.n;
for(int i=1;i<=n;++i)
for(int j=1;j<=nt.n;++j){
tmp.a[i+j-1]+=a[i]*nt.a[j];
tmp.a[i+j]+=tmp.a[i+j-1]/B;
tmp.a[i+j-1]%=B;
}
for(int i=1;i<=tmp.n;++i){
tmp.a[i+1]+=tmp.a[i]/B;
tmp.a[i]%=B;
}
tmp.work();
return tmp;
}
inline huge_int operator / (const int &nt) const {
huge_int tmp;
tmp.clear();
int x=0;
tmp.n=n;
for(int i=n;i>=1;--i){
x=x*B+a[i];
tmp.a[i]=x/nt;
x%=nt;
}
tmp.work();
return tmp;
}
inline huge_int operator += (const huge_int &nt) { return *this=*this+nt; }
inline huge_int operator -= (const huge_int &nt) { return *this=*this-nt; }
inline huge_int operator *= (const huge_int &nt) { return *this=*this*nt; }
inline huge_int operator /= (const int &nt) { return *this=*this/nt; }
};
inline huge_int gcd(huge_int a,huge_int b) {
int na=0,nb=0;
while(!(a.a[1]&1)) na++,a/=2;
while(!(b.a[1]&1)) nb++,b/=2;
int x=min(na,nb);
while(a!=b){
if(a<b) swap(a,b);
a=a-b;
while(!(a.a[1]&1)) a/=2;
}
huge_int t;
t=2;
while(x--) a*=t;
return a;
}
}
using namespace Huge_int;
using namespace std;
huge_int a,b;
signed main(){
if(fopen("T1.in","r")){
freopen("T1.in","r",stdin);
freopen("T1.out","w",stdout);
}
a.rd();b.rd();
gcd(a,b).wrt();
return 0;
}
矩阵乘法和快速幂：
namespace Matrix {
using namespace std;
const int p=2009;
struct matrix {
int a[MAXN+5][MAXN+5];
int n,m;
inline void set(const int &nx) {
for(int i=1;i<=nx;++i) a[i][i]=1;
n=m=nx;
}
inline void clear(){ n=m=0;memset(a,0,sizeof(a)); }
inline matrix operator * (const matrix &b) const {
matrix ret;ret.clear();
ret.n=n;ret.m=b.m;
for(int i=1;i<=n;++i)for(int j=1;j<=m;++j)for(int k=1;k<=b.m;++k)
ret.a[i][j]=(ret.a[i][j]+a[i][k]*b.a[k][j]%p)%p;
return ret;
}
inline matrix operator *= (const matrix &b) { return *this=*this*b; }
inline void wrt() {
for(int i=1;i<=n;++i){
for(int j=1;j<=m;++j) printf("%d ",a[i][j]);
putchar('\n');
}
}
};
inline matrix power(matrix a,int b) {
matrix ret;ret.clear();ret.set(a.n);
for(;b;a*=a,b>>=1)if(b&1)ret*=a;
return ret;
}
}
拉链hash：
namespace Hash{
const int mod=100007;
struct HashTable {
struct Link { int val1,val2,next;}E[N];
int head[mod],cnt;
inline void add(int u,int v,int w) {
E[++cnt].next=head[u];
E[cnt].val1=v;
E[cnt].val2=w;
head[u]=cnt;
}
inline void insert(int x,int k) {
int s=x%mod;
add(s,x,k);
}
inline void clear() {
memset(head,0,sizeof(head));
cnt=0;
}
inline int locate(int x) {
int s=x%mod;
for(int i=head[s];i;i=E[i].next)
if(E[i].val1==x) return E[i].val2;
return -1;
}
}H;
}
