高精度运算合集
花了一个下午打的，我太难了QwQ
使用的是重载运算符，代码不长，比某些人只打四个运算符就能打三百行好太多了。
目前只支持正整数运算，可以算出负数（如
每个运算符都写了高精和低精。
太高级的运算符写不来，但日常做题绝对够用
主要面向对象：刚学高精的新手们
复杂度挺高的，没压位（FFT，NTT什么的不会），大佬们勿喷
注意：‘
好了上代码吧，请尽情欣赏这个艺术品吧。
2021.9.4 更新string转bigint
#include <bits/stdc++.h>
using namespace std;
struct bigint
{
int n, a[10010];
bool f;
bigint()
{
clear();
}
void clear()
{
n = 1, f = 1;
memset(a, 0, sizeof(a));
}
void read()
{
cin >> n;
for (int i = n; i >= 1; i--)
cin >> a[i];
}
void write()
{
if (!f)
cout << '-';
for (int i = n; i >= 1; i--)
cout << a[i];
cout << endl;
}
void operator=(int x)
{
clear();
if (x == 0)
return;
if (x < 0)
x = -x, f = 0;
n = 0;
while (x)
{
a[++n] = x % 10;
x /= 10;
}
}
void operator=(string x)
{
clear();
int st = 0;
if (x[0] == '-')
f = 0, st++;
n = 0;
int len = x.size();
for (int i = st; i < len; i++)
a[++n] = x[len - i - 1] - '0';
}
void operator=(bigint x)
{
clear();
n = x.n;
f = x.f;
for (int i = 1; i <= n; i++)
a[i] = x.a[i];
}
bool operator==(bigint x)
{
if (n != x.n)
return 0;
for (int i = n; i >= 1; i++)
if (a[i] != x.a[i])
return 0;
return 1;
}
bool operator!=(bigint x)
{
return !operator==(x);
}
bool operator<(bigint x)
{
if (n == x.n)
for (int i = n; i >= 1; i--)
if (a[i] != x.a[i])
return a[i] < x.a[i];
return n < x.n;
}
bool operator>(bigint x)
{
if (n == x.n)
for (int i = n; i >= 1; i--)
if (a[i] != x.a[i])
return a[i] > x.a[i];
return n > x.n;
}
bool operator<=(bigint x)
{
return !operator>(x);
}
bool operator>=(bigint x)
{
return !operator<(x);
}
bool operator!()
{
if (n != 1)
return 0;
return a[1] == 0;
}
bool operator==(int x)
{
bigint y;
y = x;
return operator==(y);
}
bool operator!=(int x)
{
bigint y;
y = x;
return operator!=(y);
}
bool operator<(int x)
{
bigint y;
y = x;
return operator<(y);
}
bool operator>(int x)
{
bigint y;
y = x;
return operator>(y);
}
bool operator<=(int x)
{
bigint y;
y = x;
return operator<=(y);
}
bool operator>=(int x)
{
bigint y;
y = x;
return operator>=(y);
}
bigint operator+(bigint x)
{
bigint y;
y.n = max(n, x.n);
int s = 0;
for (int i = 1; i <= y.n; i++)
{
s += a[i] + x.a[i];
y.a[i] = s % 10;
s /= 10;
}
while (s)
{
y.a[++y.n] += s % 10;
s /= 10;
}
return y;
}
bigint operator+(int x)
{
bigint y;
y = x;
return operator+(y);
}
bigint operator-(bigint x)
{
bigint y, z = *this;
if (z < x)
y.f = 0, swap(z, x);
y.n = z.n;
for (int i = 1; i <= y.n; i++)
{
if (z.a[i] < x.a[i])
{
z.a[i + 1]--;
z.a[i] += 10;
}
y.a[i] = z.a[i] - x.a[i];
}
while (y.a[y.n] == 0 && y.n > 1)
y.n--;
return y;
}
bigint operator-(int x)
{
bigint y;
y = x;
return operator-(y);
}
bigint operator*(bigint x)
{
bigint y;
for (int i = 1; i <= n; i++)
for (int j = 1; j <= x.n; j++)
y.a[i + j - 1] += a[i] * x.a[j];
y.n = n + x.n;
for (int i = 1; i < y.n; i++)
if (y.a[i] >= 10)
{
y.a[i + 1] += y.a[i] / 10;
y.a[i] %= 10;
}
while (y.a[y.n] == 0 && y.n > 1)
y.n--;
return y;
}
bigint operator*(int x)
{
bigint y;
y = x;
return operator*(y);
}
bigint operator/(bigint x)
{
bigint y, z = *this;
if (x == y)
return x;
y.n = z.n - x.n + 1;
for (int i = y.n; i >= 1; i--)
{
bigint t = x << (i - 1);
while (z >= t)
{
y.a[i]++;
z -= t;
}
}
while (y.a[y.n] == 0 && y.n > 1)
y.n--;
return y;
}
bigint operator/(int x)
{
bigint y;
y = x;
return operator/(y);
}
bigint operator%(bigint x)
{
bigint z = *this;
return z - z / x * x;
}
bigint operator%(int x)
{
bigint y;
y = x;
return operator%(y);
}
bigint operator<<(int l)
{
bigint x;
for (int i = 1; i <= n; i++)
x.a[i + l] = a[i];
x.n = n + l;
return x;
}
bigint operator>>(int l)
{
bigint x;
x.n = n - l;
for (int i = 1; i <= x.n; i++)
x.a[i] = a[i + l];
return x;
}
void operator+=(bigint x)
{
bigint z = *this;
*this = z + x;
}
void operator-=(bigint x)
{
bigint z = *this;
*this = z - x;
}
void operator*=(bigint x)
{
bigint z = *this;
*this = z * x;
}
void operator/=(bigint x)
{
bigint z = *this;
*this = z / x;
}
void operator%=(bigint x)
{
bigint z = *this;
*this = z % x;
}
void operator+=(int x)
{
bigint z = *this;
*this = z + x;
}
void operator-=(int x)
{
bigint z = *this;
*this = z - x;
}
void operator*=(int x)
{
bigint z = *this;
*this = z * x;
}
void operator/=(int x)
{
bigint z = *this;
*this = z / x;
}
void operator%=(int x)
{
bigint z = *this;
*this = z % x;
}
};喜欢的话，点个赞吧OwO