极限IO优化

namespace IO{ 
    #define BUF_SIZE 100000 
    #define OUT_SIZE 100000 
    #define ll long long 
    //fread->read 
 
    bool IOerror=0; 
    inline char nc(){ 
        static char buf[BUF_SIZE],*p1=buf+BUF_SIZE,*pend=buf+BUF_SIZE; 
        if (p1==pend){ 
            p1=buf; pend=buf+fread(buf,1,BUF_SIZE,stdin); 
            if (pend==p1){IOerror=1;return -1;} 
            //{printf("IO error!\n");system("pause");for (;;);exit(0);} 
        } 
        return *p1++; 
    } 
    inline bool blank(char ch){return ch==' '||ch=='\n'||ch=='\r'||ch=='\t';} 
    inline void read(int &x){ 
        bool sign=0; char ch=nc(); x=0; 
        for (;blank(ch);ch=nc()); 
        if (IOerror)return; 
        if (ch=='-')sign=1,ch=nc(); 
        for (;ch>='0'&&ch<='9';ch=nc())x=x*10+ch-'0'; 
        if (sign)x=-x; 
    } 
    inline void read(ll &x){ 
        bool sign=0; char ch=nc(); x=0; 
        for (;blank(ch);ch=nc()); 
        if (IOerror)return; 
        if (ch=='-')sign=1,ch=nc(); 
        for (;ch>='0'&&ch<='9';ch=nc())x=x*10+ch-'0'; 
        if (sign)x=-x; 
    } 
    inline void read(double &x){ 
        bool sign=0; char ch=nc(); x=0; 
        for (;blank(ch);ch=nc()); 
        if (IOerror)return; 
        if (ch=='-')sign=1,ch=nc(); 
        for (;ch>='0'&&ch<='9';ch=nc())x=x*10+ch-'0'; 
        if (ch=='.'){ 
            double tmp=1; ch=nc(); 
            for (;ch>='0'&&ch<='9';ch=nc())tmp/=10.0,x+=tmp*(ch-'0'); 
        } 
        if (sign)x=-x; 
    } 
    inline void read(char *s){ 
        char ch=nc(); 
        for (;blank(ch);ch=nc()); 
        if (IOerror)return; 
        for (;!blank(ch)&&!IOerror;ch=nc())*s++=ch; 
        *s=0; 
    } 
    inline void read(char &c){ 
        for (c=nc();blank(c);c=nc()); 
        if (IOerror){c=-1;return;} 
    } 
    //fwrite->write 
    struct Ostream_fwrite{ 
        char *buf,*p1,*pend; 
        Ostream_fwrite(){buf=new char[BUF_SIZE];p1=buf;pend=buf+BUF_SIZE;} 
        void out(char ch){ 
            if (p1==pend){ 
                fwrite(buf,1,BUF_SIZE,stdout);p1=buf; 
            } 
            *p1++=ch; 
        } 
        void print(int x){ 
            static char s[15],*s1;s1=s; 
            if (!x)*s1++='0';if (x<0)out('-'),x=-x; 
            while(x)*s1++=x%10+'0',x/=10; 
            while(s1--!=s)out(*s1); 
        } 
        void println(int x){ 
            static char s[15],*s1;s1=s; 
            if (!x)*s1++='0';if (x<0)out('-'),x=-x; 
            while(x)*s1++=x%10+'0',x/=10; 
            while(s1--!=s)out(*s1); out('\n'); 
        } 
        void print(ll x){ 
            static char s[25],*s1;s1=s; 
            if (!x)*s1++='0';if (x<0)out('-'),x=-x; 
            while(x)*s1++=x%10+'0',x/=10; 
            while(s1--!=s)out(*s1); 
        } 
        void println(ll x){ 
            static char s[25],*s1;s1=s; 
            if (!x)*s1++='0';if (x<0)out('-'),x=-x; 
            while(x)*s1++=x%10+'0',x/=10; 
            while(s1--!=s)out(*s1); out('\n'); 
        } 
        void print(double x,int y){ 
            static ll mul[]={1,10,100,1000,10000,100000,1000000,10000000,100000000, 
                1000000000,10000000000LL,100000000000LL,1000000000000LL,10000000000000LL, 
                100000000000000LL,1000000000000000LL,10000000000000000LL,100000000000000000LL}; 
            if (x<-1e-12)out('-'),x=-x;x*=mul[y]; 
            ll x1=(ll)floor(x); if (x-floor(x)>=0.5)++x1; 
            ll x2=x1/mul[y],x3=x1-x2*mul[y]; print(x2); 
            if (y>0){out('.'); for (size_t i=1;i<y&&x3*mul[i]<mul[y];out('0'),++i); print(x3);} 
        } 
        void println(double x,int y){print(x,y);out('\n');} 
        void print(char *s){while (*s)out(*s++);} 
        void println(char *s){while (*s)out(*s++);out('\n');} 
        void flush(){if (p1!=buf){fwrite(buf,1,p1-buf,stdout);p1=buf;}} 
        ~Ostream_fwrite(){flush();} 
    }Ostream; 
    inline void print(int x){Ostream.print(x);} 
    inline void println(int x){Ostream.println(x);} 
    inline void print(char x){Ostream.out(x);} 
    inline void println(char x){Ostream.out(x);Ostream.out('\n');} 
    inline void print(ll x){Ostream.print(x);} 
    inline void println(ll x){Ostream.println(x);} 
    inline void print(double x,int y){Ostream.print(x,y);} 
    inline void println(double x,int y){Ostream.println(x,y);} 
    inline void print(char *s){Ostream.print(s);} 
    inline void println(char *s){Ostream.println(s);} 
    inline void println(){Ostream.out('\n');} 
    inline void flush(){Ostream.flush();}
    #undef ll 
    #undef OUT_SIZE 
    #undef BUF_SIZE 
};

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