高精度模板

本模板可能存在缺陷,请阅读后使用。

众所周知,高精度一直都是非常不友好滴~,所以wljss在这里为大家提供一下重载后的结构体高精度(可处理负数,但比较符号比较的是绝对值),还是非常实用滴_.(感谢神佬@yych 的补充)

本模板不定期更新,若有错误之处还望不吝赐教,目前重载的符号有:

1.*:高精度乘法(NTT&非NTT) 2.+:高精度加法 3.-:高精度减法 4./:高精除低精 5.>>:高精度cin读入 6.<<:高精度cout输出。7.取min操作(可正可负)8.取max操作(可正可负)

另外附上NTT用到的各种素数及原根

#include<iostream>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#define LL long long
using namespace std;
int m;
const long long mod=998244353,G=3,Ginv=(mod+1)/3;
int r[240100];
LL ksm(LL a,LL b,LL mod)
{
    LL ans=1;
    for(;b;b>>=1,a=a*a%mod)
        if(b&1)ans=ans*a%mod;
    return ans;
}
void NTT(int limit,LL *l,int opt)
{
    for(int i=0;i<limit;++i)
    if(i<r[i])swap(l[i],l[r[i]]);
    for(int mid=1;mid<limit;mid<<=1)
    {
        LL wn,len=mid<<1;;
        if(opt==1)wn=ksm(G,(mod-1)/len,mod);
        else wn=ksm(Ginv,(mod-1)/len,mod);
        for(int j=0;j<limit;j+=len)
        {
            LL w=1;
            for(int k=j;k<mid+j;++k,(w*=wn)%=mod)
            {
                int x=l[k],y=w*l[k+mid]%mod;
                l[k]=(x+y)%mod;
                l[k+mid]=(x-y+mod)%mod;
            }
        }
    }
    if(opt==-1)
    {
        LL inv=ksm(limit,mod-2,mod);
        for(int i=0;i<=limit;i++) l[i]=l[i]*inv%mod;
    }
}
/*------以下为重载部分------*/ 
struct gj
{
    int len,zheng;//len:长度 zheng:正负标记0为负1为正 
    LL v[6000];
    gj(){len=0;memset(v,0,sizeof(v));zheng=1;}
    gj(int x)
    {
        if(x>=0)zheng=1;
        else x=-x,zheng=0;
        len=0;memset(v,0,sizeof(v));
        while(x)
        {
            v[++len]=x%10;
            x/=10;
        }
    }
    friend bool operator <(const gj &a,const gj &b)
    {
        if(a.len<b.len)return 1;
        if(a.len>b.len)return 0;
        for(int i=a.len;i>=1;--i)
        {
            if(a.v[i]<b.v[i])return 1;
            if(a.v[i]>b.v[i])return 0;
        }
        return 0;
    }
    friend bool operator ==(const gj &a,const gj &b)//正数 
    {
        if(a.len!=b.len)return 0;
        for(int i=a.len;i>=1;--i)
        if(a.v[i]!=b.v[i])return 0;
        return 1;
    }
    friend bool operator <=(const gj &a,const gj &b)//正数 
    {
        if(a<b)return 1;
        else if(a==b)return 1;
        else return 0;
    }
}n,mid;
ostream& operator << (ostream &out,const gj &a);
istream& operator >> (istream &in,gj &a);
gj operator -(gj a,gj b);
gj operator +(gj a,gj b);
gj operator *(gj a,gj b);
gj operator +(gj a,gj b)
{
    if(!a.zheng&&!b.zheng)
    {
        a.zheng=b.zheng=1;
        gj c=a+b;
        c.zheng=0;
        return c;
    }
    if(!a.zheng&&b.zheng)
    {
        a.zheng=b.zheng=1;
        return b-a;
    }
    if(a.zheng&&!b.zheng)
    {
        a.zheng=b.zheng=1;
        return a-b;
    }
    int len=a.len+b.len;
    gj c;
    c.len=len;
    for(int i=1;i<=len;++i)c.v[i]=a.v[i]+b.v[i];
    for(int i=1;i<=len;++i)
    {
        if(c.v[i]>=10)
        {
            ++c.v[i+1];
            c.v[i]-=10;
        }
    }
    while(c.len&&!c.v[c.len])c.len--;
    return c;
}
gj operator -(gj a,gj b)
{
    if(!a.zheng&&!b.zheng)
    {
        a.zheng=b.zheng=1;
        return b-a;
    }
    if(!a.zheng&&b.zheng)
    {
        a.zheng=1;
        gj c=a+b;
        c.zheng=0;
        return c;
    }
    if(a.zheng&&!b.zheng)
    {
        b.zheng=1;
        gj c=a+b;
        return c;
    }
    if(a.zheng&&b.zheng&&a<b)
    {
        gj c=b-a;
        c.zheng=0;
        return c;
    }
    int len=max(a.len,b.len);
    gj c;
    for(int i=1;i<=len;++i)c.v[i]=a.v[i]-b.v[i];
    c.len=len;
    for(int i=1;i<=c.len;++i)
    {
        if(c.v[i]<0)
        {
            c.v[i+1]--;
            c.v[i]+=10;
        }
    }
    while(c.len&&!c.v[c.len])c.len--;
    return c;
}
gj operator *(gj a,gj b)
{
    int limit=1,tot,l=0;
    gj c;
    a.len--;b.len--;
    for(int i=0;i<=a.len;++i)a.v[i]=a.v[i+1];a.v[a.len+1]=0;
    for(int i=0;i<=b.len;++i)b.v[i]=b.v[i+1];b.v[b.len+1]=0;
    while(limit<=a.len+b.len)limit<<=1,l++;
    for(int i=0;i<=limit;i++) r[i]=(r[i>>1]>>1) | ((i&1)<<(l-1) );
    NTT(limit,a.v,1);NTT(limit,b.v,1);
    for(int i=0;i<=limit;i++) a.v[i]=a.v[i]*b.v[i]%mod;
    NTT(limit,a.v,-1);
    for(int i=0;i<=limit;i++) c.v[i]=a.v[i];
    for(int i=0;i<=limit;i++)
    {
        if(c.v[i]>=10)
        {
            c.v[i+1]+=c.v[i]/10,c.v[i]%=10;
            if(i+1>limit) limit++;
        }
    }
    for(int i=limit;i>=0;i--)if(c.v[i]==0) limit--;else break;
    c.len=limit+1;
    for(int i=c.len;i>=1;--i)c.v[i]=c.v[i-1];c.v[0]=0;
    for(int i=1;i<=c.len;++i)swap(c.v[i],c.v[c.len-i+1]);
    if(a.zheng!=b.zheng)c.zheng=0;
    else c.zheng=1;
    return c;
}
gj operator /(gj a,long long b)
{
    gj c;int d=0;
    for(int i=a.len;i>=1;--i)
    c.v[++c.len]=((d*10+a.v[i])/b),d=(d*10+a.v[i])%b;
    for(int i=1;i<=c.len/2;++i)swap(c.v[i],c.v[c.len-i+1]);
    if(!a.len||!b||(a.zheng&&b>0)||(!a.zheng&&b<0))c.zheng=1;
    else c.zheng=0;
    while(c.v[c.len]==0&&c.len>1)--c.len;
    return c;
}
gj operator %(gj a,long long b)
{
    gj c;
    c=a-a/b*gj(b);
    return c;
}
istream& operator >> (istream &in,gj &a)//方便使用cin
{
    char lin[5010];int len;
    scanf("%s",lin+1);
    len=a.len=strlen(lin+1);
    if(lin[1]=='-')a.zheng=0,a.len--;
    else a.zheng=1;
    for(int i=1;i<=a.len;++i)a.v[i]=lin[len-i+1]-'0';
    return in;
}
ostream& operator << (ostream &out,const gj &a)//方便使用cout 
{
    if(!a.len)//一定要注意答案是0得情况 
    {
        cout<<"0";
        return out;
    }
    if(!a.zheng)cout<<"-";
    for(int i=a.len;i>=1;i--)printf("%d",a.v[i]);
    return out;
}
/*------以上为重载部分------*/ 
gj ksm(gj a,int b)
{
    gj ans=gj(1);
    for(;b;b>>=1,a=a*a)
    if(b&1)ans=ans*a;
    return ans;
}
gj Max(gj a,gj b) // yych
{
    if(a.zheng==1&&b.zheng==0) return a;
    else
    if(a.zheng==0&&b.zheng==1) return b;
    else
    {
       if(a.zheng==1)
        {
            if(a<b) return b;
            else return a;
        }
        else
        {
            if(a<b) return a;
            else return b;
        }
    }
}
gj Min(gj a,gj b) //yych
{
    if(a.zheng==1&&b.zheng==0) return b;
    else
    if(a.zheng==0&&b.zheng==1) return a;
    else
    {
         if(a.zheng==1)
        {
            if(a<b) return a;
            else return b;
        }
        else
        {
            if(a<b) return b;
            else return a;
        }
    }
}
int main()
{
    return 0;
}

上面的乘法是使用NTT来实现的,常数可能比较大,下面是正常的乘法

gj operator *(gj a,gj b)
{
    gj c;
    for(int i=1;i<=a.len;++i)
    for(int j=1;j<=b.len;++j)
    c.v[i+j-1]+=a.v[i]*b.v[j];
    c.len=a.len+b.len;
    for(int i=1;i<=c.len-1;++i)
    {
        if(c.v[i]>=10)
        {
            c.v[i+1]+=c.v[i]/10;
            c.v[i]%=10;
        }
    }
    while(c.v[c.len]==0&&c.len>1)--c.len;
    if(a.zheng!=b.zheng)c.zheng=0;
    else c.zheng=1;
    return c;
}
posted @ 2019-09-16 20:59  wljss  阅读(923)  评论(4编辑  收藏  举报