23 lines
556 B
C++
23 lines
556 B
C++
// in-place modification
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int basis(vector<ll>& a) {
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int n = a.size();
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int has = 0;
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for (int i = 63; ~i and has < n; --i) {
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for (int j = has; j < n; ++j) {
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if (a[j] & (ll(1) << i)) {
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swap(a[j], a[has]);
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break;
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}
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}
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if (not (a[has] & (ll(1) << i))) continue;
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for (int j = 0; j < n; ++j) {
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if (j == has) continue;
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if (a[j] & (ll(1) << i)) {
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a[j] ^= a[has];
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}
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}
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++has;
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}
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return has;
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}
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