Large number plus minus multiplication

The calculation problem of large numbers has always been the subject of the programming competition, and it has been done again before the Blue Bridge Cup competition. Large number of division is more difficult, has not yet to try to achieve, and then have the opportunity to continue to complement the whole good.
algorithm Analysis: three kinds of methods are similar, are bitwise operation, dynamic storage. Once the input data has been processed, it is easy to get an answer for each bit by operation.
Large number of additions

#include <iostream>#include <cstdio>#include <cstring>#include <cmath>#define MAX 1010using namespace STD;stringb;intA[max],b[max];intSum[max];intT,L1,L2;intMain () {memsetA0,sizeof(a));memset(b,0,sizeof(b));memset(Sum,0,sizeof(sum));Cin>>A;Cin>>B;BOOLflag=true;    L1=a.length (); L2=b.length (); for(inti = l1-1; I >=0; i--) a[l1-1-i]=a[i]-' 0 '; for(inti = l2-1; I >=0; i--) b[l2-1-i]=b[i]-' 0 '; for(inti =0; I < Max (L1,L2) +2; i++) {Sum[i]+=a[i]+b[i];if(Sum[i] >=Ten) {sum[i+1]+=sum[i]/Ten; sum[i]%=Ten; }    } for(inti = max-1; I >=0; i--) {if(Sum[i] = =0&& flag)Continue; flag=false;printf("%d", Sum[i]); }printf("\ n");}

Large number Subtraction

#include <iostream>#include <cstdio>#include <cstring>#define MAXusing namespace STD;CharA[max];CharB[max];CharC[max];intL1,L2;BOOLflag=false;intNum1[max],num2[max];BOOLIf_exchange ();voidExchange ();voidMinus (intx);voidPrint ();intMain () { while(Gets (a) &&gets (b)) {l1=l2=0;memset(NUM1,0,sizeof(NUM1));memset(Num2,0,sizeof(num2));memsetC0,sizeof(c)); Flag=if_exchange (); for(inti =strlen(a)-1; I >=0; i--) {num1[l1]=a[i]-' 0 ';        l1++; } for(inti =strlen(b)-1; I >=0; i--) {num2[l2]=b[i]-' 0 ';        l2++; } for(inti =0; i < L1;        i++) minus (i);    Print (); }return 0;}BOOLIf_exchange () {if(strlen(a) <strlen(b)) {Exchange ();return true; }Else if(strlen(a) = =strlen(b)) { for(inti =0; I < (int)strlen(a); i++) {if(A[i] > B[i]) Break;Else if(A[i] < b[i]) {Exchange ();return true; }Else                Continue; }    }return false;}voidExchange () {strcpy(C,a);strcpy(A, B);strcpy(B,C);return;}voidMinus (intx) {if(Num1[x] >= num2[x]) num1[x]-=num2[x];Else{num1[x+1]--; num1[x]=num1[x]+Ten-NUM2[X]; }return;}voidPrint () {intIBOOLsflag=true;if(flag)cout<<'-'; for(i = l1-1; I >=0; i--) {if(Sflag && num1[i]==0)Continue;Else{sflag=false;printf("%d", Num1[i]); }    }if(Sflag)cout<<0;cout<<endl;return;}

Large number multiplication

#include <iostream>#include <cstdio>#include <cstring>#define MAXusing namespace STD;CharA[max];intL1,L2;intLengthintNum1[max],num2[max];intsave[2*max];voidTime (intx);voidPrint ();intMain () {l1=l2=0; Length=0;memset(NUM1,0,sizeof(NUM1));memset(Num2,0,sizeof(num2));memset(Save,0,sizeof(save)); Gets (a); for(inti =strlen(a)-1; I >=0; i--) {num1[l1]=a[i]-' 0 ';    l1++; } gets (a); for(inti =strlen(a)-1; I >=0; i--) {num2[l2]=a[i]-' 0 ';    l2++; } for(inti =0; i < L1;    i++) time (i); Print ();cout<<endl;return 0;}voidTime (intx) {intASS=NUM1[X];intTem[max];intlmax=0;memset(TEM,0,sizeof(TEM)); for(inti =0; I < L2; i++) {intMid=ass*num2[i];        Tem[i]+=mid; tem[i+1]+=tem[i]/Ten; tem[i]%=Ten; lmax=i+1;if(tem[i+1]!=0) lmax++; } for(inti = x; i < X+lmax;        i++) {save[i]+=tem[i-x]; save[i+1]+=save[i]/Ten; save[i]%=Ten; Length=i;if(save[i+1]!=0) length++; }return;}voidPrint () {BOOLflag=true;intI for(i = length; I >=0; i--) {if(Flag && save[i]==0)Continue;Else{flag=false;printf("%d", Save[i]); }    }if(I <0&& flag = =true)cout<<0;return;}

Large number plus minus multiplication