NEW UPD :
This morning, I begin with BigInteger in C++
(because I usually use BigInteger in Java
). I want to check the correction about my code, so that I post this blog to hope you can check it.
Thank knst, I have more update :
I use
typedef vector<int> BigInt;
to make oneBigInteger
I use only with positive numbers.
In my code have the function
initialize one BigInt
:
BigInt a = Integer(string);
BigInt a = Integer(char[]);
BigInt a = Integer(int);
BigInt a = Integer(long long);
- I have function
print one BigInt
:
Print(BigInt);
- I have
iostream BigInt
: NEW
cin >> BigInt;
cout << BigInt;
- I have
operators on BigInt
: have NEW
BigInt + BigInt (the value return is BigInt)
BigInt + int (the value return is BigInt)
++BigInt (the value of BigInt set to BigInt+1 and the value return is BigInt)
BigInt += BigInt (no return value)
BigInt += int (no return value)
BigInt - BigInt (the value return is BigInt, that is positive numbers)
BigInt - int (the value return is BigInt)
--BigInt (the value of BigInt set to BigInt-1 and the value return is BigInt)
BigInt -= BigInt (no return value)
BigInt -= int (no return value)
BigInt * BigInt (the value return is BigInt)
BigInt * int (the value return is BigInt)
BigInt *= BigInt (no return value)
BigInt *= int (no return value)
BigInt / BigInt (the value return is BigInt) (need optimal)
BigInt / int (the value return is BigInt) (NEW - quickly)
BigInt /= BigInt (no return value)
BigInt /= int (no return value)
BigInt % BigInt (the value return is BigInt)
BigInt % int (the value return is int, that is in [0..int-1])
BigInt %= BigInt (no return value)
BigInt %= int (no return value)
NEW : Compare
BigInt - BigInt
BigInt - int
> , < , == , >= , <= (the value return is bool)
- I have
functions on BigInt
:
max(BigInt, BigInt) (the value return is BigInt)
min(BigInt, BigInt) (the value return is BigInt)
gcd(BigInt, BigInt) (the value return is BigInt)
lcm(BigInt, BigInt) (the value return is BigInt)
sqrt(BigInt) (the value return is BigInt)
NEW : quickly : knst comment (http://mirror.codeforces.com/blog/entry/16380#comment-213120)
log(int, BigInt) (the value return is int, log(int, BigInt) is small)
I hope you can check the correction of this code
Sorry for my bad English.
Hope have more comments to improve BigInt
perfectly.
This is my code :
https://github.com/Stupid-Dog/BigInteger/blob/stupid/BigInteger.cpp
http://paste.ubuntu.com/10270983/
#include <bits/stdc++.h>
using namespace std;
typedef int64_t ll;
typedef long long ll;
#define EL printf("\n")
#define pb push_back
#define FOR(i,l,r) for (int i=l;i<=r;i++)
#define FORD(i,r,l) for (int i=r;i>=l;i--)
const int base = 1e9;
typedef vector<int> BigInt;
void Set(BigInt &a) {
while (a.size() > 1 && a.back() == 0) a.pop_back();
}
void Print(BigInt a) {
Set(a);
printf("%d", (a.size() == 0) ? 0 : a.back());
FORD(i,a.size()-2,0) printf("%09d", a[i]); EL;
}
BigInt Integer(string s) {
BigInt ans;
if (s[0] == '-') return ans;
if (s.size() == 0) {ans.pb(0); return ans;}
while (s.size()%9 != 0) s = '0'+s;
for (int i=0;i<s.size();i+=9) {
int v = 0;
for (int j=i;j<i+9;j++) v = v*10+(s[j]-'0');
ans.insert(ans.begin(),v);
}
Set(ans);
return ans;
}
BigInt Integer(char c[]) {
string s = "";
FOR(i,0,strlen(c)-1) s = s + c[i];
return Integer(s);
}
BigInt Integer(ll x) {
string s = "";
while (x > 0) s = char(x%10+'0') + s, x /= 10;
return Integer(s);
}
BigInt Integer(int x) {
return Integer((ll) x);
}
void operator >> (istream &in, BigInt &a) {
string s;
getline(cin, s);
a = Integer(s);
}
void operator << (ostream &out, BigInt a) {
Print(a);
}
bool operator < (BigInt a, BigInt b) {
Set(a);
Set(b);
if (a.size() != b.size()) return (a.size() < b.size());
FORD(i,a.size()-1,0)
if (a[i] != b[i]) return (a[i] < b[i]);
return false;
}
bool operator > (BigInt a, BigInt b) {
return (b < a);
}
bool operator == (BigInt a, BigInt b) {
return (!(a < b) && !(b < a));
}
bool operator <= (BigInt a, BigInt b) {
return (a < b || a == b);
}
bool operator >= (BigInt a, BigInt b) {
return (b < a || b == a);
}
bool operator < (BigInt a, int b) {
return (a < Integer(b));
}
bool operator > (BigInt a, int b) {
return (a > Integer(b));
}
bool operator == (BigInt a, int b) {
return (a == Integer(b));
}
bool operator >= (BigInt a, int b) {
return (a >= Integer(b));
}
bool operator <= (BigInt a, int b) {
return (a <= Integer(b));
}
BigInt max(BigInt a, BigInt b) {
if (a > b) return a;
return b;
}
BigInt min(BigInt a, BigInt b) {
if (a < b) return a;
return b;
}
BigInt operator + (BigInt a, BigInt b) {
Set(a);
Set(b);
BigInt ans;
int carry = 0;
FOR(i,0,max(a.size(), b.size())-1) {
if (i < a.size()) carry += a[i];
if (i < b.size()) carry += b[i];
ans.pb(carry%base);
carry /= base;
}
if (carry) ans.pb(carry);
Set(ans);
return ans;
}
BigInt operator + (BigInt a, int b) {
return a + Integer(b);
}
BigInt operator ++ (BigInt &a) { // ++a
a = a + 1;
return a;
}
void operator += (BigInt &a, BigInt b) {
a = a + b;
}
void operator += (BigInt &a, int b) {
a = a + b;
}
BigInt operator — (BigInt a, BigInt b) {
Set(a);
Set(b);
BigInt ans;
int carry = 0;
FOR(i,0,a.size()-1) {
carry += a[i] — (i < b.size() ? b[i] : 0);
if (carry < 0) ans.pb(carry+base), carry = -1;
else ans.pb(carry), carry = 0;
}
Set(ans);
return ans;
}
BigInt operator — (BigInt a, int b) {
return a — Integer(b);
}
void operator -- (BigInt &a) { // --a
a = a — 1;
}
void operator -= (BigInt &a, BigInt b) {
a = a + b;
}
void operator -= (BigInt &a, int b) {
a = a — b;
}
BigInt operator * (BigInt a, BigInt b) {
Set(a);
Set(b);
BigInt ans;
ans.assign(a.size()+b.size(), 0);
FOR(i,0,a.size()-1) {
ll carry = 0ll;
for (int j=0;j<b.size() || carry > 0;j++) {
ll s = ans[i+j] + carry + (ll)a[i]*(j<b.size()?(ll)b[j]:0ll);
ans[i+j] = s%base;
carry = s/base;
}
}
Set(ans);
return ans;
}
BigInt operator * (BigInt a, int b) {
return a * Integer(b);
}
void operator *= (BigInt &a, BigInt b) {
a = a * b;
}
void operator *= (BigInt &a, int b) {
a = a * b;
}
BigInt operator / (BigInt a, BigInt b) {
Set(a);
Set(b);
if (b == Integer(0)) return Integer("-1");
BigInt ans, cur;
FORD(i,a.size()-1,0) {
cur.insert(cur.begin(), a[i]);
int x = 0, L = 0, R = base;
while (L <= R) {
int mid = (L+R)>>1;
if (b*Integer(mid) > cur) {
x = mid;
R = mid-1;
}
else
L = mid+1;
}
cur = cur — Integer(x-1)*b;
ans.insert(ans.begin(),x-1);
}
Set(ans);
return ans;
}
BigInt operator / (BigInt a, int b) {
Set(a);
BigInt ans;
ll cur = 0ll;
FORD(i,a.size()-1,0) {
cur = (cur*(ll)base + (ll)a[i]);
ans.insert(ans.begin(),cur/b);
cur %= b;
}
Set(ans);
return ans;
}
void operator /= (BigInt &a, BigInt b) {
a = a / b;
}
void operator /= (BigInt &a, int b) {
a = a / b;
}
BigInt operator % (BigInt a, BigInt b) {
Set(a);
Set(b);
if (b == Integer(0)) return Integer("-1");
BigInt ans;
FORD(i,a.size()-1,0) {
ans.insert(ans.begin(), a[i]);
int x = 0, L = 0, R = base;
while (L <= R) {
int mid = (L+R)>>1;
if (b*Integer(mid) > ans) {
x = mid;
R = mid-1;
}
else
L = mid+1;
}
ans = ans — Integer(x-1)*b;
}
Set(ans);
return ans;
}
int operator % (BigInt a, int b) {
Set(a);
if (b == 0) return -1;
int ans = 0;
FORD(i,a.size()-1,0)
ans = (ans*(base%b) + a[i]%b)%b;
return ans;
}
void operator %= (BigInt &a, BigInt b) {
a = a % b;
}
void operator %= (BigInt &a, int b) {
a = a % Integer(b);
}
BigInt gcd(BigInt a, BigInt b) {
Set(a);
Set(b);
while (b > Integer(0)) {
BigInt r = a%b;
a = b;
b = r;
}
Set(a);
return a;
}
BigInt lcm(BigInt a, BigInt b) {
return (a*b/gcd(a,b));
}
BigInt sqrt(BigInt a) {
BigInt x0 = a, x1 = (a+1)/2;
while (x1 < x0) {
x0 = x1;
x1 = (x1+a/x1)/2;
}
return x0;
}
BigInt pow(BigInt a, BigInt b) {
if (b == Integer(0)) return Integer(1);
BigInt tmp = pow(a, b/2);
if (b%2 == 0) return tmp * tmp;
return tmp * tmp * a;
}
BigInt pow(BigInt a, int b) {
return pow(a,(Integer(b)));
}
int log(int n, BigInt a) { // log_n(a)
Set(a);
int ans = 0;
while (a > Integer(1)) {
ans++;
a /= n;
}
return ans;
}
int main()
{
BigInt B; cin >> B;
BigInt A = Integer("123456789");
BigInt C = Integer(123456789ll);
int x; x = 123456789;
if (B <= A) cout << A - B;
else {
cout << "-";
cout << B - A;
}
cout << A + B; Print(A + x);
cout << A * B; Print(A * x);
cout << A / B; Print(A / x);
cout << A % B; printf("%d\n", A % x);
C = ++A; ++B; C += B + x;
Print(A); Print(B); Print(C);
cout << max(A,B);
cout << min(A,B);
cout << gcd(A,B);
cout << lcm(A,B);
cout << sqrt(A);
printf("%d %d %d\n", log(2,A), log(10,B), log(5,C));
A = Integer(16); x = 12;
cout << pow(A,B);
cout << pow(A,x);
return 0;
}