misc/magics.h

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Last update: 2025-12-09 07:33:19+07:00

Code

#pragma GCC optimize("Ofast,unroll-loops")       // unroll long, simple loops
#pragma GCC target("avx2,fma")                   // vectorizing code
#pragma GCC target("lzcnt,popcnt,abm,bmi,bmi2")  // for fast bitset operation

using namespace __gnu_pbds;  // ordered_set, gp_hash_table
using namespace __gnu_cxx;   // rope

// fast map
const int RANDOM = chrono::high_resolution_clock::now().time_since_epoch().count();
struct chash {  // customize hash function for gp_hash_table
  int operator()(int x) const { return x ^ RANDOM; }
};
gp_hash_table<int, int, chash> table;

/* ordered set
    find_by_order(k): returns an iterator to the k-th element (0-based)
    order_of_key(k): returns the number of elements in the set that are strictly less than k
*/
template <class T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

/*  rope
    rope <int> cur = v.substr(l, r - l + 1);
    v.erase(l, r - l + 1);
    v.insert(v.mutable_begin(), cur);
*/

#line 1 "misc/magics.h"
#pragma GCC optimize("Ofast,unroll-loops")       // unroll long, simple loops
#pragma GCC target("avx2,fma")                   // vectorizing code
#pragma GCC target("lzcnt,popcnt,abm,bmi,bmi2")  // for fast bitset operation

using namespace __gnu_pbds;  // ordered_set, gp_hash_table
using namespace __gnu_cxx;   // rope

// fast map
const int RANDOM = chrono::high_resolution_clock::now().time_since_epoch().count();
struct chash {  // customize hash function for gp_hash_table
  int operator()(int x) const { return x ^ RANDOM; }
};
gp_hash_table<int, int, chash> table;

/* ordered set
    find_by_order(k): returns an iterator to the k-th element (0-based)
    order_of_key(k): returns the number of elements in the set that are strictly less than k
*/
template <class T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

/*  rope
    rope <int> cur = v.substr(l, r - l + 1);
    v.erase(l, r - l + 1);
    v.insert(v.mutable_begin(), cur);
*/