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-rw-r--r--math/bigint.cpp275
1 files changed, 0 insertions, 275 deletions
diff --git a/math/bigint.cpp b/math/bigint.cpp
deleted file mode 100644
index 6f83a93..0000000
--- a/math/bigint.cpp
+++ /dev/null
@@ -1,275 +0,0 @@
-// base and base_digits must be consistent
-constexpr ll base = 1'000'000;
-constexpr ll base_digits = 6;
-struct bigint {
- vll a; ll sign;
-
- bigint() : sign(1) {}
-
- bigint(ll v) {*this = v;}
-
- bigint(const string &s) {read(s);}
-
- void operator=(const bigint& v) {
- sign = v.sign;
- a = v.a;
- }
-
- void operator=(ll v) {
- sign = 1;
- if (v < 0) sign = -1, v = -v;
- a.clear();
- for (; v > 0; v = v / base)
- a.push_back(v % base);
- }
-
- bigint operator+(const bigint& v) const {
- if (sign == v.sign) {
- bigint res = v;
- for (ll i = 0, carry = 0; i < max(sz(a), sz(v.a)) || carry; ++i) {
- if (i == sz(res.a))
- res.a.push_back(0);
- res.a[i] += carry + (i < sz(a) ? a[i] : 0);
- carry = res.a[i] >= base;
- if (carry)
- res.a[i] -= base;
- }
- return res;
- }
- return *this - (-v);
- }
-
- bigint operator-(const bigint& v) const {
- if (sign == v.sign) {
- if (abs() >= v.abs()) {
- bigint res = *this;
- for (ll i = 0, carry = 0; i < sz(v.a) || carry; ++i) {
- res.a[i] -= carry + (i < sz(v.a) ? v.a[i] : 0);
- carry = res.a[i] < 0;
- if (carry) res.a[i] += base;
- }
- res.trim();
- return res;
- }
- return -(v - *this);
- }
- return *this + (-v);
- }
-
- void operator*=(ll v) {
- if (v < 0) sign = -sign, v = -v;
- for (ll i = 0, carry = 0; i < sz(a) || carry; ++i) {
- if (i == sz(a)) a.push_back(0);
- ll cur = a[i] * v + carry;
- carry = cur / base;
- a[i] = cur % base;
- }
- trim();
- }
-
- bigint operator*(ll v) const {
- bigint res = *this;
- res *= v;
- return res;
- }
-
- friend pair<bigint, bigint> divmod(const bigint& a1, const bigint& b1) {
- ll norm = base / (b1.a.back() + 1);
- bigint a = a1.abs() * norm;
- bigint b = b1.abs() * norm;
- bigint q, r;
- q.a.resize(sz(a.a));
- for (ll i = sz(a.a) - 1; i >= 0; i--) {
- r *= base;
- r += a.a[i];
- ll s1 = sz(r.a) <= sz(b.a) ? 0 : r.a[sz(b.a)];
- ll s2 = sz(r.a) <= sz(b.a) - 1 ? 0 : r.a[sz(b.a) - 1];
- ll d = (base * s1 + s2) / b.a.back();
- r -= b * d;
- while (r < 0) r += b, --d;
- q.a[i] = d;
- }
- q.sign = a1.sign * b1.sign;
- r.sign = a1.sign;
- q.trim();
- r.trim();
- return make_pair(q, r / norm);
- }
-
- bigint operator/(const bigint& v) const {
- return divmod(*this, v).first;
- }
-
- bigint operator%(const bigint& v) const {
- return divmod(*this, v).second;
- }
-
- void operator/=(ll v) {
- if (v < 0) sign = -sign, v = -v;
- for (ll i = sz(a) - 1, rem = 0; i >= 0; --i) {
- ll cur = a[i] + rem * base;
- a[i] = cur / v;
- rem = cur % v;
- }
- trim();
- }
-
- bigint operator/(ll v) const {
- bigint res = *this;
- res /= v;
- return res;
- }
-
- ll operator%(ll v) const {
- if (v < 0) v = -v;
- ll m = 0;
- for (ll i = sz(a) - 1; i >= 0; --i)
- m = (a[i] + m * base) % v;
- return m * sign;
- }
-
- void operator+=(const bigint& v) {
- *this = *this + v;
- }
- void operator-=(const bigint& v) {
- *this = *this - v;
- }
- void operator*=(const bigint& v) {
- *this = *this * v;
- }
- void operator/=(const bigint& v) {
- *this = *this / v;
- }
-
- bool operator<(const bigint& v) const {
- if (sign != v.sign) return sign < v.sign;
- if (sz(a) != sz(v.a))
- return sz(a) * sign < sz(v.a) * v.sign;
- for (ll i = sz(a) - 1; i >= 0; i--)
- if (a[i] != v.a[i])
- return a[i] * sign < v.a[i] * sign;
- return false;
- }
-
- bool operator>(const bigint& v) const {
- return v < *this;
- }
- bool operator<=(const bigint& v) const {
- return !(v < *this);
- }
- bool operator>=(const bigint& v) const {
- return !(*this < v);
- }
- bool operator==(const bigint& v) const {
- return !(*this < v) && !(v < *this);
- }
- bool operator!=(const bigint& v) const {
- return *this < v || v < *this;
- }
-
- void trim() {
- while (!a.empty() && !a.back()) a.pop_back();
- if (a.empty()) sign = 1;
- }
-
- bool isZero() const {
- return a.empty() || (sz(a) == 1 && a[0] == 0);
- }
-
- bigint operator-() const {
- bigint res = *this;
- res.sign = -sign;
- return res;
- }
-
- bigint abs() const {
- bigint res = *this;
- res.sign *= res.sign;
- return res;
- }
-
- ll longValue() const {
- ll res = 0;
- for (ll i = sz(a) - 1; i >= 0; i--)
- res = res * base + a[i];
- return res * sign;
- }
-
- void read(const string& s) {
- sign = 1;
- a.clear();
- ll pos = 0;
- while (pos < sz(s) && (s[pos] == '-' || s[pos] == '+')) {
- if (s[pos] == '-') sign = -sign;
- ++pos;
- }
- for (ll i = sz(s) - 1; i >= pos; i -= base_digits) {
- ll x = 0;
- for (ll j = max(pos, i - base_digits + 1); j <= i; j++)
- x = x * 10 + s[j] - '0';
- a.push_back(x);
- }
- trim();
- }
-
- friend istream& operator>>(istream& stream, bigint& v) {
- string s;
- stream >> s;
- v.read(s);
- return stream;
- }
-
- friend ostream& operator<<(ostream& stream, const bigint& v) {
- if (v.sign == -1) stream << '-';
- stream << (v.a.empty() ? 0 : v.a.back());
- for (ll i = sz(v.a) - 2; i >= 0; --i)
- stream << setw(base_digits) << setfill('0') << v.a[i];
- return stream;
- }
-
- static vll karatsubaMultiply(const vll& a, const vll& b) {
- ll n = sz(a);
- vll res(n + n);
- if (n <= 32) {
- for (ll i = 0; i < n; i++)
- for (ll j = 0; j < n; j++)
- res[i + j] += a[i] * b[j];
- return res;
- }
- ll k = n >> 1;
- vll a1(a.begin(), a.begin() + k);
- vll a2(a.begin() + k, a.end());
- vll b1(b.begin(), b.begin() + k);
- vll b2(b.begin() + k, b.end());
- vll a1b1 = karatsubaMultiply(a1, b1);
- vll a2b2 = karatsubaMultiply(a2, b2);
- for (ll i = 0; i < k; i++) a2[i] += a1[i];
- for (ll i = 0; i < k; i++) b2[i] += b1[i];
- vll r = karatsubaMultiply(a2, b2);
- for (ll i = 0; i < sz(a1b1); i++) r[i] -= a1b1[i];
- for (ll i = 0; i < sz(a2b2); i++) r[i] -= a2b2[i];
- for (ll i = 0; i < sz(r); i++) res[i + k] += r[i];
- for (ll i = 0; i < sz(a1b1); i++) res[i] += a1b1[i];
- for (ll i = 0; i < sz(a2b2); i++) res[i + n] += a2b2[i];
- return res;
- }
-
- bigint operator*(const bigint& v) const {
- vll a(this->a.begin(), this->a.end());
- vll b(v.a.begin(), v.a.end());
- while (sz(a) < sz(b)) a.push_back(0);
- while (sz(b) < sz(a)) b.push_back(0);
- while (sz(a) & (sz(a) - 1))
- a.push_back(0), b.push_back(0);
- vll c = karatsubaMultiply(a, b);
- bigint res;
- res.sign = sign * v.sign;
- for (ll i = 0, carry = 0; i < sz(c); i++) {
- ll cur = c[i] + carry;
- res.a.push_back(cur % base);
- carry = cur / base;
- }
- res.trim();
- return res;
- }
-};
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