elva

void subtract(char *numa, char *numb,char *result)//計(jì)算減
            {
            char *pna = findend(numa);//指向numa的一個(gè)指針。point numa      pna 指向減數(shù)的最低位，
            char *pnb = findend(numb);//指向numb的一個(gè)指針                 //pnb 指向被減數(shù)的最低位，
            int  along=(int)strlen(numa);//標(biāo)記數(shù)字a的長(zhǎng)度；
            int  blong=(int)strlen(numb);//標(biāo)記數(shù)字b的長(zhǎng)度；
            int  times = 0;         // 標(biāo)記要計(jì)算多少次。
            int  carry=0;           //存貯借位
            int  clear0=0;          //消除結(jié)果最前面無(wú)用的'0'  13-5 = 08 的效果！！
            int  isnegative=0;      //用來(lái)加上被減數(shù)大于減數(shù)時(shí)補(bǔ)上最后一個(gè)負(fù)號(hào)
            Node *head,   // 用于存貯頭指針
            *pstart,  // 用于存貯計(jì)算時(shí)的首指針
            *pnew;    //作于申請(qǐng)新結(jié)點(diǎn)
            head = pstart =new Node;//初始化首結(jié)點(diǎn)和頭結(jié)點(diǎn)。
            pstart -> data = 0;
            pstart -> next = NULL;
            pstart -> ahead = NULL;
            if (abigerb(numa ,numb))
            times = strlen(numa);//比較兩個(gè)字符串長(zhǎng)度，以大的作為循環(huán)次數(shù)
            else //交換位置以降低難度
            {
            times = strlen(numb);//讓數(shù)（字符串）長(zhǎng)的減去數(shù)（字符串）短的
            pna = findend(numb);//交換指針
            pnb = findend(numa);
            along=(int)strlen(numb);//標(biāo)記數(shù)字a的長(zhǎng)度；
            blong=(int)strlen(numa);//標(biāo)記數(shù)字b的長(zhǎng)度；
            isnegative=1;//標(biāo)記最后要加上負(fù)號(hào)
            }
            while ((times-- && (times>=0))|| carry != 0)//carry != 0 說(shuō)沒有借位時(shí)
            {
            if(!pstart->next)//如果當(dāng)前為空結(jié)點(diǎn)，則申請(qǐng)新結(jié)點(diǎn)
            {
            pnew = new Node;
            pnew -> data = 0;
            pnew -> next = NULL;
            pnew -> ahead = pstart;
            pstart -> next = pnew;
            }
            if(times<0)//如果計(jì)算完之后，借位等于1，，說(shuō)明必然為負(fù)值;
            {
            pstart -> data  = -3 ;//讓它等于負(fù)號(hào) '-'//-3來(lái)源于負(fù)號(hào)與0相差3。。                break;
            }
            else
            {
            if ( *pna == *pnb )//減數(shù)等于被減數(shù)時(shí)。結(jié)果等于直截相減的結(jié)果；并置借位為0
            {
            if(carry==0)pstart -> data = (*pna-48)-(*pnb-48); //111-11的情況
            else
            {
            pstart->data = (*pna-48)-(*pnb-48)+10 -carry;//1121-1112
            carry=1;
            }
            }
            if( *pna > *pnb )//減數(shù)大于被減數(shù)時(shí)。結(jié)果等于直截相減的結(jié)果；并置借位為0
            {
            pstart -> data = (*pna-48)-(*pnb-48)-carry;  //存貯個(gè)位
            carry=0;
            }
            else if( *pna < *pnb )//說(shuō)明被減數(shù)大于減數(shù)，讓結(jié)果加10，相當(dāng)于借位 (carry)為1
            {
            if(times>0) pstart->data = (*pna-48)-(*pnb-48)+10 -carry;//13-5的情況作為新值
            else  pstart->data = (*pnb-48)-(*pna-48) -carry; //3-5  作為當(dāng)前的新值
            carry=1;
            }
            }
            pstart = pstart -> next;          //結(jié)點(diǎn)移動(dòng)
            blong--;
            if(blong>0)pnb--;//指針移向被減數(shù)高位
            else *pnb=48;//之后相減就變?yōu)榱?不作任何運(yùn)算，其實(shí)可以優(yōu)化的。但代碼會(huì)長(zhǎng)！而且還需要重新開結(jié)點(diǎn)。所以放棄；
            pna--;//被數(shù)指針移動(dòng)，
            }
            if(isnegative==1)////加上負(fù)號(hào)處理。增加一長(zhǎng)度并置為負(fù)號(hào)
            {
            pnew = new Node;
            pnew -> data = 0;
            pnew -> next = NULL;
            pnew -> ahead = pstart;
            pstart -> next = pnew;
            pstart->data=-3;//因?yàn)閷ふ益湵淼慕Y(jié)尾點(diǎn)要統(tǒng)一加48。又因?yàn)?#8216;-’是45。所以等于‘-3’
            }
            pstart =head;//尋找鏈表的結(jié)尾點(diǎn)
            while(pstart->next != 0)
            {
            pstart->data += 48;//!!<<<因?yàn)槲覀兊妮敵鍪亲址Ｋ栽俅思由?8>>>>  逆順輸出
            pstart = pstart->next ;
            }
            int tip = 0;//轉(zhuǎn)為字符串用
            clear0=0;//  消除結(jié)果最前面無(wú)用的'0'  13-5 = 08 的效果  ..>>修改字符串的首指針
            pstart = pstart->ahead ;//找有效字
            while(pstart != 0)//輸出正序的結(jié)果；
            {
            if (clear0==0 && ((int)pstart->data)==48&&pstart->ahead!=0)//  消除結(jié)果最前面無(wú)用的'0'
            ;//不輸出任何東西
            else
            result[tip++] = pstart->data;
            if(((int)pstart->data)!=48&&((int)pstart->data)!=45)clear0=1;//'－'號(hào)
            pstart = pstart->ahead ;
            }
            result[tip] = '\0';
            pstart =head;  //釋放空間
            while(pstart->next != 0)
            {
            pnew = pstart->next ;delete pstart;
            pstart =pnew;
            }
            return ;
            }
            

void multiply(char *numa, char *numb ,char *result)//用來(lái)儲(chǔ)結(jié)果的)//計(jì)算乘積
            {
            char *pna = findend(numa);//指向numa的一個(gè)指針。point numa      pna 指向乘數(shù)的最低位，
            char *pnb = findend(numb);//指向numb的一個(gè)指針                 //pnb 指向被乘數(shù)的最低位，
            int along=(int)strlen(numa);//標(biāo)記數(shù)字a的長(zhǎng)度；
            int blong=(int)strlen(numb);//標(biāo)記數(shù)字b的長(zhǎng)度；
            int  carry=0,temp_result;//存貯進(jìn)位  和臨時(shí)結(jié)果的
            Node *head,   // 用于存貯頭指針
            *pstart,  // 用于存貯計(jì)算時(shí)的首指針
            *pnew,    //作于申請(qǐng)新結(jié)點(diǎn)
            *pgo;     //作為每計(jì)算完一行時(shí)，回到下一行起始節(jié)點(diǎn)用,移位標(biāo)致來(lái)用
            head = pstart =new Node;//初始化首結(jié)點(diǎn)和頭結(jié)點(diǎn)。
            pstart -> data = 0;
            pstart -> next = NULL;
            pstart -> ahead = NULL;
            while (along--)
            {
            pgo = pstart;//保存進(jìn)位點(diǎn)
            blong = (int)strlen(numb);//初始化長(zhǎng)度
            pnb = findend(numb); //初始化指針
            while ((blong-- && (blong>=0))|| carry != 0)
            {
            if(!pstart->next)//如果當(dāng)前為空結(jié)點(diǎn)，則申請(qǐng)新結(jié)點(diǎn)
            {
            pnew = new Node;
            pnew -> data = 0;
            pnew -> next = NULL;
            pnew -> ahead = pstart;
            pstart -> next = pnew;
            }
            if(blong<0)temp_result = carry ;//處理只有進(jìn)位的情況
            else temp_result =(pstart->data+(*pna-48)*(*pnb-48)+carry);//自身值+新值+進(jìn)位作為新值
            pstart -> data = temp_result%10;  //存貯個(gè)位
            carry = temp_result/10;           //存貯進(jìn)位
            pstart = pstart -> next;          //結(jié)點(diǎn)移動(dòng)
            pnb--; //指針移向被乘數(shù)高位
            }
            pstart = pgo->next; //前進(jìn)一個(gè)位置；
            pna--;   //指針移向乘數(shù)高位
            }
            pstart =head;//尋找鏈表的結(jié)尾點(diǎn)
            while(pstart->next != 0)
            {
            pstart->data += 48;//!!<<<因?yàn)槲覀兊妮敵鍪亲址Ｋ栽俅思由?8>>>>  逆順輸出
            pstart = pstart->next ;
            }
            int tip = 0;//轉(zhuǎn)為字符串用
            pstart = pstart->ahead ;//找有效字
            while(pstart != 0)//輸出正序的結(jié)果；
            {
            result[tip++] = pstart->data;
            pstart = pstart->ahead ;
            }
            result[tip] = '\0';
            pstart =head;  //釋放空間
            while(pstart->next != 0)
            {
            pnew = pstart->next ;delete pstart;
            pstart =pnew;
            }
            return ;
            }
            

void divide2( char *numa, char *numb,char *result,char *remainder)//計(jì)算除法2
            {
            char one[]="1";//臨時(shí)字符串....
            char one2[]="1";//
            char zero[]="0";//
            char numb2[6048];//
            char tempstr[6018]="";//臨時(shí)字符串
            int  ia=0,ia2=0;//tempstr的指示器
            bool  moveon=false;//翻轉(zhuǎn)牌
            char *pna = numa;//指向numa的一個(gè)指針。point numa      pna 指向減數(shù)的最低位，
            char *pnb = findend(numb);//指向numb的一個(gè)指針                 //pnb 指向被減數(shù)的最低位，
            Node *head,   // 用于存貯頭指針
            *pstart,  // 用于存貯計(jì)算時(shí)的首指針
            *pnew;    //作于申請(qǐng)新結(jié)點(diǎn)
            head = pstart =new Node;//初始化首結(jié)點(diǎn)和頭結(jié)點(diǎn)。
            pstart -> data = 0;
            pstart -> next = NULL;
            pstart -> ahead = NULL;
            moveon = false;
            while(*pna)
            {
            if(!pstart->next)//如果當(dāng)前為空結(jié)點(diǎn)，則申請(qǐng)新結(jié)點(diǎn)
            {
            pnew = new Node;
            pnew -> data = 0;
            pnew -> next = NULL;
            pnew -> ahead = pstart;
            pstart -> next = pnew;
            }
            ia=(int)strlen(tempstr);//取的長(zhǎng)度
            tempstr[ia++] = *(pna++);
            tempstr[ia] ='\0'; //轉(zhuǎn)換為字符串
            if(tempstr[0]=='0')//處理高位也是0的那種 如00
            {
            ia2=0;
            while(tempstr[ia2]=='0')++ia2;
            while(ia2>=1)//清除無(wú)用的0
            {
            ia=ia2-1;
            tempstr[ia]=tempstr[ia2];
            --ia2;
            }
            tempstr[++ia2]='\0';
            }
            while(abigerb(tempstr,numb)>0)//如果tempstr大于等于numb
            {
            if(tempstr[0]=='0')//處理高位也是0的那種 如00----此乃冗余代碼，留做記念用
            {
            ia2=0;
            while(tempstr[ia2]=='0')++ia2;
            if(ia==ia2 )
            {
            moveon = true;
            break;
            }
            }
            strcpy(numb2,numb);
            subtract(tempstr, numb,tempstr);//A-B
            strcpy(numb,numb2);
            if(tempstr[0]=='-')//若判斷的不準(zhǔn)，變?yōu)榱素?fù)數(shù)就再加上B。。
            {
            strcpy(numb2,numb);
            addition(tempstr, numb,tempstr);//A-B
            strcpy(numb,numb2);
            ia2=0; //修正之后的長(zhǎng)度。因?yàn)榧臃ㄖ形醋鲐?fù)數(shù)運(yùn)算
            ia=0;  //為了消除最后的那一個(gè)負(fù)號(hào)，整體向前移動(dòng)。
            while(tempstr[ia2]!='\0')++ia2;
            while(ia2>=1)//清除無(wú)用的0
            {
            tempstr[ia]=tempstr[ia+1];
            ++ia;
            --ia2;
            }
            tempstr[ia]='\0';
            moveon = true;
            break;
            }
            pstart->data++ ; //結(jié)果自加
            moveon = true;
            }
            if(moveon) pstart = pstart -> next;          //結(jié)點(diǎn)移動(dòng)
            }
            strcpy(remainder,tempstr);//存貯余數(shù)
            int tip = 0;//轉(zhuǎn)為字符串用
            pstart =head;//尋找鏈表的結(jié)尾點(diǎn)
            while(pstart->next != 0)
            {
            pstart->data += 48;//!!<<<因?yàn)槲覀兊妮敵鍪亲址Ｋ栽俅思由?8>>>>  逆順輸出
            result[tip++] = pstart->data;
            pstart = pstart->next ;
            }
            result[tip] = '\0';//存貯結(jié)果
            pstart =head;  //釋放空間
            while(pstart->next != 0)
            {
            pnew = pstart->next ;delete pstart;
            pstart =pnew;
            }
            return ;
            }