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Diffstat (limited to 'math/transforms/bitwiseTransforms.cpp')
| -rw-r--r-- | math/transforms/bitwiseTransforms.cpp | 12 |
1 files changed, 12 insertions, 0 deletions
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) +} |