C + + Large-number precision calculation (with decimal points) __c++

Header file:

Wtnumber.h:interface for the Cwtnumber class. #if!defined (afx_wtnumber_h__92e62b40_ 491A_4A75_AB89_FFB160DB2343__INCLUDED_) #define AFX_WTNUMBER_H__92E62B40_491A_4A75_AB89_FFB160DB2343__INCLUDED_ # If _msc_ver > 1000 #pragma once #endif//_msc_ver > 1000 #define INT_BIT_MAX 255 #define FLOAT_BIT_MAX 255 Class                     Cwtnumber {private:int intbits;                   /* Integer digit */int floatbits;                   /* Decimal effective digit/char infinite;                       /* Infinity */char sign;       /* Symbol */char Intpart[int_bit_max];   /* Integer part */char Floatpart[float_bit_max];
* * Small number of parts/private:char* M_SZ;
    Public:/* arithmetic function pointer type. */typedef void (*PFNCALC) (const cwtnumber&,const cwtnumber&,cwtnumber&);
    Cwtnumber ();
    Cwtnumber (const char* sznum);
    ~cwtnumber ();
    /* Convert to String * * char* ToString ();
    void Freestring ();
    /* Initialize Wtnumber to 0.*/void Initwtnumbertozero ();
    /* Determine how many character spaces are required to store the Wtnumber conversion string. * * int strlenbywtnumber ();
    /* Converts from string to wtnumber.*/void Strtowtnumber (const char *arr);
    /* Converts from Wtnumber to string. */void Wtnumbertostr (char *szbuf);
    /* Adjust digit, delete the highest integer digit is 0 and the lowest decimal place is the digit of 0. */void Adjustbits ();
    /* Move the decimal point, delta=0 does not move, delta<0 to the left, delta>0 to the right to move. * * void movefloatpoint (int delta);
    /* Make infinity/void Makeinfinite ();
    /* Compare 2 number size */int wtcompare (const cwtnumber& n) const;
    /* To determine whether 0/int iszero () const;

    /* Assignment Number Overload * * cwtnumber& operator= (const cwtnumber& N);
    /* operator overload */Cwtnumber operator+ (const cwtnumber& N);
    Cwtnumber operator-(const cwtnumber& N);
    Cwtnumber operator* (const cwtnumber& N);
    Cwtnumber operator/(const cwtnumber& N);
    cwtnumber& operator+= (const cwtnumber& N);
    cwtnumber& operator-= (const cwtnumber& N);
    cwtnumber& operator*= (const cwtnumber& N); cwtnumber& operator/=(const cwtnumber& N);
    BOOL Operator> (const cwtnumber& N);
    BOOL Operator>= (const cwtnumber& N);
    BOOL operator< (const cwtnumber& N);
    BOOL Operator<= (const cwtnumber& N);
    BOOL operator== (const cwtnumber& N);
    BOOL Operator!= (const cwtnumber& N);
    /* addition */static void Wtadd (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res);
    /* multiplication */static void wtmultiply (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res);
    /* Subtraction */static void Wtsubtract (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res);
    /* Division */static void Wtdivide (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res);
/* The result is returned according to the arithmetic function */static char *result (const char *val1,const char *val2,pfncalc pfncalc);


}; #endif//!defined (AFX_WTNUMBER_H__92E62B40_491A_4A75_AB89_FFB160DB2343__INCLUDED_)

Source file:

WTNumber.cpp:implementation of the Cwtnumber class. #include <string.h> #include < stdlib.h> #include "WTNumber.h"/////////////////////////////////////////////////////////////////////// Construction/destruction//////////////////////////////////////////////////////////////////////CWTNumber::
Cwtnumber () {Initwtnumbertozero ();}
    Cwtnumber::cwtnumber (const char* sznum) {Initwtnumbertozero ();
Strtowtnumber (Sznum);
    } cwtnumber::~cwtnumber () {freestring ();} void Cwtnumber::freestring () {if (M_SZ) delete []M_SZ;
M_sz=null; } void Cwtnumber::initwtnumbertozero () {memset (this,0,sizeof (Cwtnumber));} int Cwtnumber::strlenbywtnumber () {i
    NT len = floatbits+intbits+1;    if (intbits==0) len++;    /*. 1--> 0.1*/if (floatbits) len++; /* '.'        */if (sign) len++;    /* '-' */if (infinite) return 11;
* * #INFINITE/return len; } void Cwtnumber::sTrtowtnumber (const char *arr) {char *point;
    Initwtnumbertozero ();
        if (*arr== '-')/* If it is a negative number * * arr++;
    Sign=1;
    } point=strchr (arr, '. ');    if (point)/* Find the decimal */{int n=intbits=point-arr;    /* Calculates the integer digital/while (n)/* integer digits not ==0 the loop/{intpart[intbits-n]=arr[n-1]-' 0 ';
        * * will be the number of low existing low standard elements * * n--;
            while (*++point) {floatpart[floatbits]=*point-' 0 ';
        floatbits++;
        } else/* Description does not write a decimal point, all integers. * * {int n=intbits=strlen (arr);
            while (n) {intpart[intbits-n]=arr[n-1]-' 0 ';
        n--;
    } adjustbits (); 
    /* processing-conditions of 0 and 0/if (floatbits==0) {if (intbits==0 | | intbits==1&&intpart[0]==0) sign=0;
    } void Cwtnumber::wtnumbertostr (char *szbuf) {int n=intbits,c;
    memset (Szbuf,0,strlenbywtnumber ());
       if (sign)/* If it is a negative number * *szbuf++= '-';
        } if (infinite) {strcat (szbuf, "#INFINITE");
    Return
        while (n) {szbuf[intbits-n]=intpart[n-1]+ ' 0 ';
    n--;    } c=0;
        /* Whether to add 0*/if (intbits==0) {strcat (szbuf, "0");
    C=1;
    } if (floatbits) strcat (Szbuf, ".");
    n=0;
        while (n<floatbits) {szbuf[intbits+1+n+c]=floatpart[n]+ ' 0 ';
    n++;
    } void Cwtnumber::adjustbits () {while (intbits>1&&intpart[intbits-1]==0) intbits--;
while (floatbits&&floatpart[floatbits-1]==0) floatbits--;
        } void Cwtnumber::movefloatpoint (int delta) {/* delta<0 moves the decimal point to the left, Delta>0 moves the decimal point to the right (Delta) {
        Cwtnumber N=*this;
        Initwtnumbertozero ();
        Sign=n.sign;
            if (delta<0) {int i;
            Delta=-delta;
            for (i=delta;i<n.intbits;i++) {intpart[intbits++]=n.intpart[i]; for (i=delta-1;i>=0;i--) {Floatpart[floatbits++]=n.intpart[i];
            for (i=0;i<n.floatbits;i++) {floatpart[floatbits++]=n.floatpart[i];
            } else {int i;
            for (i=delta;i<n.floatbits;i++)/* Processing decimal parts/{Floatpart[floatbits++]=n.floatpart[i]; for (i=delta-1;i>=0;i--)/* Decimal to Integer part * * {Intpart[intbits++]=n.floa
            Tpart[i];
            for (i=0;i<n.intbits;i++)/* Integer part */{intpart[intbits++]=n.intpart[i];
}} adjustbits ();

} void Cwtnumber::makeinfinite () {infinite=1;} int Cwtnumber::wtcompare (const cwtnumber& N) Const {/* First is the comparison symbol */if (sign==0&&n.sign!=0)/* PN1 is a positive number,    PN2 is a negative number */return 1;
      /* >*/else if (sign!=0&&n.sign==0)/* PN1 is a negative number, PN2 is a positive number * *  return-1; /* <*/else/////{///////////* Compare Integer part/if (intbits>n.intbits)//PN1 integer digit multiple */RE
        Turn sign?-1:1;
        else if (intbits<n.intbits) return sign?1:-1;    else//* integer digit same */{int i=intbits-1; /* refers to the highest bit */while (i>=0) {if (Intpart[i]>n.intpart[i]) Retu
                RN Sign?-1:1;
                else if (Intpart[i]<n.intpart[i]) return sign?1:-1;
            else i--;
            }/* The integer part is the same, compared to the decimal part of the */for (i=0;i<floatbits&&i<n.floatbits;)
                {if (Floatpart[i]>n.floatpart[i]) return sign?-1:1;
                else if (Floatpart[i]<n.floatpart[i]) return sign?1:-1;
            else i++;
            } if (i<floatbits) return sign?-1:1;
           if (i<n.floatbits) return sign?1:-1; return 0;
    /* Equality */}} int Cwtnumber::iszero () const {if (floatbits==0&&intbits==0) return 1;
    if (floatbits==0&&intbits==1&&intpart[0]==0) return 1;
return 0; } void Cwtnumber::wtadd (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res) {Res.initwtnumbertozero (
    );
        if (n1.sign^n2.sign)/* XOR/{Cwtnumber rn2=n2;
        Rn2.sign=n1.sign;
    Wtsubtract (N1,rn2,res);
        else */* the same number */{int maxfloatbits=n1.floatbits>n2.floatbits?n1.floatbits:n2.floatbits;    int addbit=0;
        /* Carry value */int i,j;
            for (i=maxfloatbits-1;i>=0;i--) {int value=n1.floatpart[i]+n2.floatpart[i]+addbit;    ADDBIT=VALUE/10; * To see if more than 10.
        Set Carry value * * RES.FLOATPART[I]=VALUE%10;
        } res.floatbits=maxfloatbits; * * To this, the decimal part of the calculation completed./For (j=0;j<n1.intbits| | j<n2.intbits;j++) {int value=n1.intpart[j]+n2.intpart[j]+addbit;
            ADDBIT=VALUE/10;
            res.intpart[j]=value%10;
        res.intbits++;
            } if (addbit>0) {res.intpart[j]=addbit;
        res.intbits++;    } res.sign=n1.sign;
    /* Decision Symbol */res.adjustbits (); } void Cwtnumber::wtmultiply (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res) {Cwtnumber z1=n1,
    Z2=N2;
    Cwtnumber sum;
    int i,j; Sum.
    Initwtnumbertozero ();
    Res.initwtnumbertozero (); Z1.
    Movefloatpoint (z1.floatbits); Z2.
    Movefloatpoint (z2.floatbits);    /* COMPUTE Z1*Z2 * * for (i=0;i<z2.intbits;i++) {cwtnumber tmp;
        /* Store temporary product/int addbit=0;
        Tmp.intbits=z1.intbits+i;
            for (j=0;j<z1.intbits;j++) {int value = Z2.intpart[i]*z1.intpart[j]+addbit;
            ADDBIT=VALUE/10;
        tmp.intpart[j+i]=value%10;
   } if (addbit) {tmp.intpart[j+i]=addbit;         tmp.intbits++;
        } wtadd (Sum,tmp,res);
    Sum=res;
    } res=sum;
    Res.movefloatpoint (-(n1.floatbits+n2.floatbits));
/* Judging symbol, the number is negative/if (n1.sign^n2.sign) res.sign=1; } void Cwtnumber::wtsubtract (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res) {Res.initwtnumberto
    Zero ();
        if (n1.sign^n2.sign)/* Cwtnumber rn2=n2;
        Rn2.sign=n1.sign;
    Wtadd (N1,rn2,res); else *///{int cmp=n1.
        Wtcompare (N2);
        int swapflag,i,maxfloatbits,subtractbit;    if (cmp==0) return;
        /* Equality there is no need to subtract. * * swapflag=n1.sign==0?cmp==-1:cmp==1;
        Const cwtnumber* pn1=&n1;
        Const cwtnumber* pn2=&n2;
            if (swapflag) {const Cwtnumber *T=PN1;
            PN1=PN2;
        pn2=t;
        } maxfloatbits=pn1->floatbits>pn2->floatbits?pn1->floatbits:pn2->floatbits;    subtractbit=0; /* Abdication Value */* First calculate the decimal part of the * * (i=maxfloatbits-1;i>=0;i--) {if (pn1->floatpart[i]-subtractbit<pn2-&gt
                ; floatpart[i]) {int value=pn1->floatpart[i]-pn2->floatpart[i]-subtractbit+10;
                Subtractbit=1;
            Res.floatpart[i]=value;
                else {int value=pn1->floatpart[i]-pn2->floatpart[i]-subtractbit;
                subtractbit=0;
            Res.floatpart[i]=value;
        }} res.floatbits=maxfloatbits; /* This decimal part is calculated./For (i=0;i<pn1->intbits| |
                i<pn2->intbits;i++) {if (Pn1->intpart[i]-subtractbit<pn2->intpart[i]) {
                int value=pn1->intpart[i]-pn2->intpart[i]-subtractbit+10;
                Subtractbit=1;
            Res.intpart[i]=value; else {int value=pn1->intpart[i]-pn2->intpart[I]-subtractbit;
                subtractbit=0;
            Res.intpart[i]=value;
        } res.intbits++; } res.sign=swapflag?!    N1.sign:n1.sign;
    /* Decision Symbol */res.adjustbits (); } void Cwtnumber::wtdivide (const cwtnumber& n1,const cwtnumber& n2,cwtnumber& Res) {Cwtnumber z1=n1,z2=
    N2;
    int deta=z2.floatbits-z1.floatbits; Z1.
    Movefloatpoint (z1.floatbits); Z2.
    Movefloatpoint (z2.floatbits);
    Res.initwtnumbertozero (); if (N1.
    Iszero ()) return; if (N2.
        Iszero ()) {res.sign=n1.sign;
        Res.makeinfinite ();
    return;                } z1.sign=z2.sign=0;
            /* Uniform symbol for ease of comparison size */while (z1.intbits!=z2.intbits) {/* ensures digital parity, which takes a lot of time/if (z1.intbits<z2.intbits) { Z1.
            Movefloatpoint (1);
        deta--; else {Z2.
            Movefloatpoint (1);
        deta++; }} while (res.floatbits< (INT_BIT_MAX/2)) {INT cmp=z1.
      Wtcompare (Z2);  int n=10;
        Cwtnumber Mulres,subres; if (cmp==-1) {/*z1<z2*/z1.
            Movefloatpoint (1);
            res.floatpart[res.floatbits++]=0;
        Continue
            else if (cmp==0) {/*z1==z2*/res.floatpart[res.floatbits++]=1;
        Break
            do {* * * Find business/cwtnumber tmp;
            Tmp.intpart[0]=--n;
            Tmp.intbits=1;
        Wtmultiply (Z2,tmp,mulres); while (Cmp=mulres.
        Wtcompare (z1)) ==1);
        Res.floatpart[res.floatbits++]=n;
        if (cmp==0) break;
        Wtsubtract (Z1,mulres,subres); Subres.
        Movefloatpoint (1);
    Z1=subres;
    } res.movefloatpoint (1);
    Res.movefloatpoint (DETA);
/* Judging symbol, the number is negative/if (n1.sign^n2.sign) res.sign=1;
    } char *cwtnumber::result (const char *val1,const char *val2,pfncalc pfncalc) {Cwtnumber n1,n2,res; N1.
    Strtowtnumber (VAL1); N2.
    Strtowtnumber (VAL2);
    Pfncalc (N1,n2,res); return Res.
ToString (); } char* CwtnumBer::tostring () {freestring ();
    M_sz=new Char[strlenbywtnumber ()];
    Wtnumbertostr (M_SZ);
return M_SZ;
        } cwtnumber& cwtnumber::operator= (const cwtnumber& N) {if (this!=&n) {freestring ();
        memcpy (this,&n,sizeof (Cwtnumber));
        if (N.M_SZ) {m_sz=strdup (N.M_SZ);
} return *this;
    } cwtnumber cwtnumber::operator+ (const cwtnumber& N) {cwtnumber res;
    Cwtnumber::wtadd (*this,n,res);
return res;
    } cwtnumber cwtnumber::operator-(const cwtnumber& N) {cwtnumber res;
    Cwtnumber::wtsubtract (*this,n,res);
return res;
    } cwtnumber cwtnumber::operator* (const cwtnumber& N) {cwtnumber res;
    Cwtnumber::wtmultiply (*this,n,res);
return res;
    } cwtnumber cwtnumber::operator/(const cwtnumber& N) {cwtnumber res;
    Cwtnumber::wtdivide (*this,n,res);
return res;
    } cwtnumber& cwtnumber::operator+= (const cwtnumber& N) {cwtnumber n1=*this,n2=n; CWtnumber::wtadd (N1,n2,*this);
return *this;
    } cwtnumber& cwtnumber::operator-= (const cwtnumber& N) {cwtnumber n1=*this,n2=n;
    Cwtnumber::wtsubtract (N1,n2,*this);
return *this;
    } cwtnumber& cwtnumber::operator*= (const cwtnumber& N) {cwtnumber n1=*this,n2=n;
    Cwtnumber::wtmultiply (N1,n2,*this);
return *this;
    } cwtnumber& cwtnumber::operator/= (const cwtnumber& N) {cwtnumber n1=*this,n2=n;
    Cwtnumber::wtdivide (N1,n2,*this);
return *this;  BOOL Cwtnumber::operator> (const cwtnumber& N) {return wtcompare (n) ==1;} bool Cwtnumber::operator>= (const cwtnumber& N) {return wtcompare (n)!=-1: bool cwtnumber::operator< (const cwtnumber& N) {return Wtco
Mpare (n) ==-1; BOOL Cwtnumber::operator<= (const cwtnumber& N) {return wtcompare (n)!=1;} bool cwtnumber::operator== (const C wtnumber& N) {return wtcompare (n) ==0: bool cwtnumber::operator!= (const cwtnumber& N) {return wtcomPare (n)!=0; }

Use Demo:

#include <stdio.h>
#include "WTNumber.h"

int main ()
{
    char sz1[256]= "";
    Char sz2[256]= "";
    Puts ("Please enter two digits:");
    while (scanf ("%s%s", SZ1,SZ2)!=-1) {Cwtnumber N1 (sz1)
        , N2 (SZ2);
        printf ("Addition of two numbers: \n%s\n", (N1+N2). ToString ());
        printf ("Subtract two results: \n%s\n", (N1-N2). ToString ());
        printf ("Multiply by two results: \n%s\n", (N1*N2). ToString ());
        printf ("Two number division result: \n%s\n", (N1/N2). ToString ());
        Puts ("Please enter two digits:");
    }
    return 0;
}

Run Result:
Please enter two digits:
13 7
The result of adding two numbers:
20
Subtract the result of two numbers:
6
Multiply the results by two numbers:
91
Divide the result of two numbers:
1.85714285714285714285714285714285714285714285714285714285714285714285714285714285714285714285714285714285714285714285714 285714