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#define rg registerconst int maxn=2005,bas=10000;struct jie{	int num[maxn],len;	bool jud;	jie(){		memset(num,0,sizeof(num));		len=jud=0;	}	friend bool operator <(const jie& A,const jie& B){		if(A.len
   
    B.len) return 0;		for(rg int i=A.len;i>=1;i--){			if(A.num[i]
    
     B.num[i]) return 0;		}		return 0;	}	friend jie operator + (const jie& A,const jie& B){		rg jie C;		C.len=std::max(A.len,B.len);		for(rg int i=1;i<=C.len;i++){			C.num[i]+=A.num[i]+B.num[i];			if(C.num[i]>=bas){				C.num[i]-=bas;				C.num[i+1]++;			}		}		if(C.num[C.len+1]) C.len++;		return C;	}	friend jie operator -(const jie& A,const jie& B) {		rg jie C;		int js[maxn];		if(A
     
      =A.num[i]){					C.num[i]=B.num[i]+js[i]-A.num[i];				} else {					C.num[i]=B.num[i]+js[i]-A.num[i]+bas;					js[i+1]-=1;				}			}			C.jud=1;		} else {			C.len=A.len;			for(rg int i=1;i<=C.len;i++){				if(A.num[i]+js[i]>=B.num[i]){					C.num[i]=A.num[i]+js[i]-B.num[i];				} else {					C.num[i]=A.num[i]+js[i]-B.num[i]+bas;					js[i+1]-=1;				}			}			C.jud=0;		}		while(!C.num[C.len]) C.len--;		return C;	}	friend jie operator * (const jie& A,const jie& B){		rg jie C;		C.len=A.len+B.len;		for(rg int i=1;i<=A.len;i++){			for(rg int j=1;j<=B.len;j++){				C.num[i+j-1]+=A.num[i]*B.num[j];				if(C.num[i+j-1]>=bas){					C.num[i+j]+=C.num[i+j-1]/bas;					C.num[i+j-1]%=bas;				}			}		}		if(!C.num[C.len]) C.len--;		return C;	}	friend jie operator /(const jie &A,const int &B){		rg jie C;		C.len=A.len;		rg long long nans=0;		for(rg int i=A.len;i>=1;i--){			nans=nans*bas+A.num[i];			if(nans>=B){				C.num[i]=nans/B;				nans%=B;			}		}		while(!C.num[C.len]) C.len--;		return C;	}	friend int operator %(const jie &A,const int &B){		rg long long nans=0;		for(rg int i=A.len;i>=1;i--){			nans=nans*bas+A.num[i];			if(nans>=B) nans%=B;		}		return nans;	}	void read(rg int val){		len=0,jud=0,memset(num,0,sizeof(num));		while(val){			num[++len]=val%bas;			val/=bas;		}	}	void autoread(){		char s[maxn];		scanf("%s",s+4);		rg int len2=strlen(s+4);		s[0]=s[1]=s[2]=s[3]='0';		len=0;		for(rg int i=len2+3;i>=4;i-=4){			num[++len]=(s[i-3]-'0')*1000+(s[i-2]-'0')*100+(s[i-1]-'0')*10+s[i]-'0';		}		while(num[len] && !len) len--;	}	void write(){		if(len && jud) printf("-");		if(!len) printf("0\n");		if(len) printf("%d",num[len]);		for(rg int i=len-1;i>=1;i--){			printf("%04d",num[i]);		}		printf("\n");	}};