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-rw-r--r--math/transforms/all.cpp62
-rw-r--r--math/transforms/andTransform.cpp21
-rw-r--r--math/transforms/bitwiseTransforms.cpp12
-rw-r--r--math/transforms/fft.cpp6
-rw-r--r--math/transforms/ntt.cpp43
-rw-r--r--math/transforms/orTransform.cpp21
-rw-r--r--math/transforms/xorTransform.cpp21
7 files changed, 53 insertions, 133 deletions
diff --git a/math/transforms/all.cpp b/math/transforms/all.cpp
deleted file mode 100644
index ebed881..0000000
--- a/math/transforms/all.cpp
+++ /dev/null
@@ -1,62 +0,0 @@
-/*constexpr ll mod = 998244353; @\hl{NTT only}@
-constexpr ll root = 3;*/
-
-using cplx = complex<double>;
-
-//void fft(vector<ll> &a, bool inverse = 0) { @\hl{NTT, xor, or, and}@
-void fft(vector<cplx>& a, bool inverse = 0) {
- int n = sz(a);
- for (int i = 0, j = 1; j < n - 1; ++j) {
- for (int k = n >> 1; k > (i ^= k); k >>= 1);
- if (j < i) swap(a[i], a[j]);
- }
- static vector<cplx> ws(2, 1);
- for (static int k = 2; k < n; k *= 2) {
- ws.resize(n);
- cplx w = polar(1.0, acos(-1.0) / k);
- for (int i=k; i<2*k; i++) ws[i] = ws[i/2] * (i % 2 ? w : 1);
- }
- for (int s = 1; s < n; s *= 2) {
- /*ll ws = powMod(root, (mod - 1) / s >> 1, mod); @\hl{NTT only}@
- if (inverse) ws = powMod(ws, mod - 2, mod);*/
- for (int j = 0; j < n; j += 2 * s) {
- //ll w = 1; @\hl{NTT only}@
- for (int k = 0; k < s; k++) {
- /*ll u = a[j + k], t = a[j + s + k] * w; @\hl{NTT only}@
- t %= mod;
- a[j + k] = (u + t) % mod;
- a[j + s + k] = (u - t + mod) % mod;
- w = (w * ws) % mod;*/
- /*ll u = a[j + k], t = a[j + s + k]; @\hl{xor only}@
- a[j + k] = u + t;
- a[j + s + k] = u - t;*/
- /*if (!inverse) { @\hl{or only}@
- a[j + k] = u + t;
- a[j + s + k] = u;
- } else {
- a[j + k] = t;
- a[j + s + k] = u - t;
- }*/
- /*if (!inverse) { @\hl{and only}@
- a[j + k] = t;
- a[j + s + k] = u + t;
- } else {
- a[j + k] = t - u;
- a[j + s + k] = u;
- }*/
- cplx u = a[j + k], t = a[j + s + k];
- t *= (inverse ? conj(ws[s + k]) : ws[s + k]);
- a[j + k] = u + t;
- a[j + s + k] = u - t;
- if (inverse) a[j + k] /= 2, a[j + s + k] /= 2;
- }}}
- /*if (inverse) { @\hl{NTT only}@
- ll div = powMod(n, mod - 2, mod);
- for (ll i = 0; i < n; i++) {
- a[i] = (a[i] * div) % mod;
- }}*/
- /*if (inverse) { @\hl{xor only}@
- for (ll i = 0; i < n; i++) {
- a[i] /= n;
- }}*/
-}
diff --git a/math/transforms/andTransform.cpp b/math/transforms/andTransform.cpp
index ab2bd40..1fd9f5c 100644
--- a/math/transforms/andTransform.cpp
+++ b/math/transforms/andTransform.cpp
@@ -1,17 +1,8 @@
-void fft(vector<cplx>& a, bool inverse = 0) {
+void fft(vector<ll>& a, bool inv = false) {
int n = sz(a);
- for (int i = 0, j = 1; j < n - 1; ++j) {
- for (int k = n >> 1; k > (i ^= k); k >>= 1);
- if (j < i) swap(a[i], a[j]);
- }
for (int s = 1; s < n; s *= 2) {
- for (int j = 0; j < n; j+= 2 * s) {
- for (int k = 0; k < s; k++) {
- ll u = a[j + k], t = a[j + s + k];
- if (!inverse) {
- a[j + k] = t;
- a[j + s + k] = u + t;
- } else {
- a[j + k] = t - u;
- a[j + s + k] = u;
-}}}}}
+ for (int i = 0; i < n; i += 2 * s) {
+ for (int j = i; j < i + s; j++) {
+ ll& u = a[j], &v = a[j + s];
+ tie(u, v) = inv ? pair(v - u, u) : pair(v, u + v);
+}}}}
diff --git a/math/transforms/bitwiseTransforms.cpp b/math/transforms/bitwiseTransforms.cpp
new file mode 100644
index 0000000..7d1f80d
--- /dev/null
+++ b/math/transforms/bitwiseTransforms.cpp
@@ -0,0 +1,12 @@
+void fft(vector<ll>& a, bool inv = false) {
+ int n = sz(a);
+ for (int s = 1; s < n; s *= 2) {
+ for (int i = 0; i < n; i += 2 * s) {
+ for (int j = i; j < i + s; j++) {
+ ll& u = a[j], &v = a[j + s];
+ tie(u, v) = inv ? pair(v - u, u) : pair(v, u + v); // AND
+ //tie(u, v) = inv ? pair(v, u - v) : pair(u + v, u); //OR
+ //tie(u, v) = pair(u + v, u - v); // XOR
+ }}}
+ //if (inv) for (ll& x : a) x /= n; // XOR (careful with MOD)
+}
diff --git a/math/transforms/fft.cpp b/math/transforms/fft.cpp
index 53a2d8d..2bd95b2 100644
--- a/math/transforms/fft.cpp
+++ b/math/transforms/fft.cpp
@@ -1,6 +1,6 @@
using cplx = complex<double>;
-void fft(vector<cplx>& a, bool inverse = 0) {
+void fft(vector<cplx>& a, bool inv = false) {
int n = sz(a);
for (int i = 0, j = 1; j < n - 1; ++j) {
for (int k = n >> 1; k > (i ^= k); k >>= 1);
@@ -16,8 +16,8 @@ void fft(vector<cplx>& a, bool inverse = 0) {
for (int j = 0; j < n; j += 2 * s) {
for (int k = 0; k < s; k++) {
cplx u = a[j + k], t = a[j + s + k];
- t *= (inverse ? conj(ws[s + k]) : ws[s + k]);
+ t *= (inv ? conj(ws[s + k]) : ws[s + k]);
a[j + k] = u + t;
a[j + s + k] = u - t;
- if (inverse) a[j + k] /= 2, a[j + s + k] /= 2;
+ if (inv) a[j + k] /= 2, a[j + s + k] /= 2;
}}}}
diff --git a/math/transforms/ntt.cpp b/math/transforms/ntt.cpp
index e1e4588..18d5bd8 100644
--- a/math/transforms/ntt.cpp
+++ b/math/transforms/ntt.cpp
@@ -1,28 +1,23 @@
-constexpr ll mod = 998244353;
-constexpr ll root = 3;
+constexpr ll mod = 998244353, root = 3;
-void fft(vector<ll>& a, bool inverse = 0) {
+void fft(vector<ll>& a, bool inv = false) {
int n = sz(a);
- for (int i = 0, j = 1; j < n - 1; ++j) {
- for (int k = n >> 1; k > (i ^= k); k >>= 1);
- if (j < i) swap(a[i], a[j]);
+ auto b = a;
+ ll r = inv ? powMod(root, mod - 2, mod) : root;
+
+ for (int s = n / 2; s > 0; s /= 2) {
+ ll ws = powMod(r, (mod - 1) / (n / s), mod), w = 1;
+ for (int j = 0; j < n / 2; j += s) {
+ for (int k = j; k < j + s; k++) {
+ ll u = a[j + k], t = a[j + s + k] * w % mod;
+ b[k] = (u + t) % mod;
+ b[n/2 + k] = (u - t + mod) % mod;
+ }
+ w = w * ws % mod;
+ }
+ swap(a, b);
}
- for (int s = 1; s < n; s *= 2) {
- ll ws = powMod(root, (mod - 1) / s >> 1, mod);
- if (inverse) ws = powMod(ws, mod - 2, mod);
- for (int j = 0; j < n; j+= 2 * s) {
- ll w = 1;
- for (int k = 0; k < s; k++) {
- ll u = a[j + k], t = a[j + s + k] * w;
- t %= mod;
- a[j + k] = (u + t) % mod;
- a[j + s + k] = (u - t + mod) % mod;
- w *= ws;
- w %= mod;
- }}}
- if (inverse) {
+ if (inv) {
ll div = powMod(n, mod - 2, mod);
- for (ll i = 0; i < n; i++) {
- a[i] *= div;
- a[i] %= mod;
-}}}
+ for (auto& x : a) x = x * div % mod;
+}}
diff --git a/math/transforms/orTransform.cpp b/math/transforms/orTransform.cpp
index fdb5bb8..eb1da44 100644
--- a/math/transforms/orTransform.cpp
+++ b/math/transforms/orTransform.cpp
@@ -1,17 +1,8 @@
-void fft(vector<ll>& a, bool inverse = 0) {
+void fft(vector<ll>& a, bool inv = false) {
int n = sz(a);
- for (int i = 0, j = 1; j < n - 1; ++j) {
- for (int k = n >> 1; k > (i ^= k); k >>= 1);
- if (j < i) swap(a[i], a[j]);
- }
for (int s = 1; s < n; s *= 2) {
- for (int j = 0; j < n; j+= 2 * s) {
- for (int k = 0; k < s; k++) {
- ll u = a[j + k], t = a[j + s + k];
- if (!inverse) {
- a[j + k] = u + t;
- a[j + s + k] = u;
- } else {
- a[j + k] = t;
- a[j + s + k] = u - t;
-}}}}}
+ for (int i = 0; i < n; i += 2 * s) {
+ for (int j = i; j < i + s; j++) {
+ ll& u = a[j], &v = a[j + s];
+ tie(u, v) = inv ? pair(v, u - v) : pair(u + v, u);
+}}}}
diff --git a/math/transforms/xorTransform.cpp b/math/transforms/xorTransform.cpp
index 48e4df2..f9d1d82 100644
--- a/math/transforms/xorTransform.cpp
+++ b/math/transforms/xorTransform.cpp
@@ -1,17 +1,10 @@
-void fft(vector<ll>& a, bool inverse = 0) {
+void fft(vector<ll>& a, bool inv = false) {
int n = sz(a);
- for (int i = 0, j = 1; j < n - 1; ++j) {
- for (int k = n >> 1; k > (i ^= k); k >>= 1);
- if (j < i) swap(a[i], a[j]);
- }
for (int s = 1; s < n; s *= 2) {
- for (int j = 0; j < n; j+= 2 * s) {
- for (int k = 0; k < s; k++) {
- ll u = a[j + k], t = a[j + s + k];
- a[j + k] = u + t;
- a[j + s + k] = u - t;
+ for (int i = 0; i < n; i += 2 * s) {
+ for (int j = i; j < i + s; j++) {
+ ll& u = a[j], &v = a[j + s];
+ tie(u, v) = pair(u + v, u - v);
}}}
- if (inverse) {
- for (ll i = 0; i < n; i++) {
- a[i] /= n;
-}}}
+ if (inv) for (ll& x : a) x /= n;
+}
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