Skip to content

Commit

Permalink
partition point finding, and some other helpful (maybe) functionality
Browse files Browse the repository at this point in the history
  • Loading branch information
@caterpillow
caterpillow authored Dec 4, 2024
1 parent 3f488dc commit 9a5ec8a
Showing 1 changed file with 140 additions and 15 deletions.
155 changes: 140 additions & 15 deletions byot.html
View file
Original file line number Diff line number Diff line change
Expand Up @@ -19,12 +19,14 @@ <h1>Build your own treap!</h1>
Usage: click on stuff u want, don't click on stuff you don't want. <br>
You can right click a disabled checkbox/dropdown to enable all its prerequisites. <br>
Half this site is written by ChatGPT so don't judge too harshly. <br>
If you have any suggestions or find any bugs (highly likely), my discord is caterpillow<br>
If you have any suggestions or find any bugs (highly likely), leave a comment on the blog. <br>
<br>
See the <a href="https://codeforces.com/blog/entry/136858" target="_blank">codeforces blog post</a> for usage examples.
<br>
</div>
<hr>


<style>
.container {
display: flex;
Expand Down Expand Up @@ -105,6 +107,7 @@ <h1>Build your own treap!</h1>
<label><input type="checkbox" id="find_option"> Include find</label><br>
<label><input type="checkbox" id="ins_option"> Include point insert</label><br>
<label><input type="checkbox" id="del_option"> Include point deletion</label><br>
<label><input type="checkbox" id="mod_option"> Include point modification</label><br>
</div>
<hr>

Expand All @@ -116,6 +119,16 @@ <h1>Build your own treap!</h1>
<label><input type="checkbox" id="findi_option"> Include find by index</label><br>
<label><input type="checkbox" id="insi_option"> Include point insert by index</label><br>
<label><input type="checkbox" id="deli_option"> Include point deletion by index</label><br>
<label><input type="checkbox" id="modi_option"> Include point modification by index</label><br>
<label><input type="checkbox" id="rot_option"> Include rotation</label><br>
</div>
<hr>

<div>
<label><input type="checkbox" id="partition_key"> Find partition key </label><br>
<label><input type="checkbox" id="partition_index"> Find partition index </label><br>
<label><input type="checkbox" id="cumulative_partition_key"> Find cumulative partition key </label><br>
<label><input type="checkbox" id="cumulative_partition_index"> Find cumulative partition index </label><br>
</div>
</div>

Expand Down Expand Up @@ -191,11 +204,14 @@ <h1>Build your own treap!</h1>
<label><input type="checkbox" id="order_option"> Include order (finds index of a node)</label><br>
<label><input type="checkbox" id="root_option"> Include root (returns the root of some treap node)</label><br>
</div>
<hr>

<div>
<label><input type="checkbox" id="treap_beats"> Enable treap beats template</label><br>
</div>
</div>
</div>
<hr>
<label><input type="checkbox" id="treap_beats"> Enable treap beats template</label><br>
<hr>
Warnings:
<!-- Warning area -->
<div id="warnings" class="warning"></div>
Expand Down Expand Up @@ -266,6 +282,14 @@ <h1>Build your own treap!</h1>
let namespace_treap = false;
let treap_beats = false;
let root_option = false;
let rot_option = false;
let mod_option = false;
let modi_option = false;

let partition_key = false;
let partition_index = false;
let cumulative_partition_key = false;
let cumulative_partition_index = false;


// Static dependencies graph
Expand Down Expand Up @@ -332,7 +356,17 @@ <h1>Build your own treap!</h1>
["treap_beats", "range_update_index"],
["val_type", "enable_value"],
["range_agg", "enable_value"],
["root_option", "par_option"]
["root_option", "par_option"],
["rot_option", "spliti_option"],
["rot_option", "merge_option"],
["mod_option", "key_type"],
["modi_option", "size_option"],
["partition_key", "key_type"],
["partition_index", "size_option"],
["cumulative_partition_key", "key_type"],
["cumulative_partition_key", "range_agg"],
["cumulative_partition_index", "size_option"],
["cumulative_partition_index", "range_agg"]
];

const sortedDependencies = topsort(edges);
Expand Down Expand Up @@ -504,6 +538,13 @@ <h1>Build your own treap!</h1>
treap_beats = document.getElementById("treap_beats").checked;
enable_value = document.getElementById("enable_value").checked;
root_option = document.getElementById("root_option").checked;
rot_option = document.getElementById("rot_option").checked;
mod_option = document.getElementById("mod_option").checked;
modi_option = document.getElementById("modi_option").checked;
partition_key = document.getElementById("partition_key").checked;
partition_index = document.getElementById("partition_index").checked;
cumulative_partition_key = document.getElementById("cumulative_partition_key").checked;
cumulative_partition_index = document.getElementById("cumulative_partition_index").checked;


clearWarnings();
Expand Down Expand Up @@ -868,13 +909,27 @@ <h1>Build your own treap!</h1>
}

if (del_option) {
if (comments) code += `void del(ptr& n, ${key_type} k) {\n`
code += ' if (!n) return;\n'
if (comments) code += '// returns pointer to deleted node\n'
code += `ptr del(ptr& n, ${key_type} k) {\n` +
' if (!n) return nullptr;\n'
if (push) code += ' push(n);\n'
code += ' if (n->key == k) { n = merge(n->l, n->r); return; }\n' +
' if (k <= n->key) del(n->l, k);\n' +
' else del(n->r, k);\n'
if (pull) ' pull(n);\n'
code += ' if (n->key == k) { ptr ret = n; n = merge(n->l, n->r); return ret; }\n' +
' ptr ret = k <= n->key ? del(n->l, k) : del(n->r, k);\n'
if (pull) code += ' pull(n);\n'
code += ' return ret;\n' +
'}\n\n'
}

if (mod_option) {
if (comments) code += '// performs an arbitrary operation on some node\n'
code += 'template <typename Op>\n' +
`void modify(ptr n, ${key_type} k, Op op) {\n` +
' if (!n) return;\n'
if (push) code += ' push(n);\n'
code += ' if (n->key == k) op(n);\n' +
' else if (k <= n->key) modify(n->l, k, op);\n' +
' else modify(n->r, k, op);\n'
if (pull) code += ' pull(n);\n'
code += '}\n\n'
}

Expand Down Expand Up @@ -920,13 +975,83 @@ <h1>Build your own treap!</h1>
}

if (deli_option) {
code += 'void deli(ptr& n, int i) {\n' +
if (comments) code += '// returns pointer to deleted node\n'
code += 'ptr deli(ptr& n, int i) {\n' +
' if (!n) return nullptr;\n'
if (push) code += ' push(n);\n'
code += ' if (i == sz(n->l)) { ptr ret = n; n = merge(n->l, n->r); return ret; }\n' +
' ptr ret = i <= sz(n->l) ? deli(n->l, i) : deli(n->r, i - 1 - sz(n->l));\n'
if (pull) code += ' pull(n);\n'
code += ' return ret;\n' +
'}\n\n'
}

if (modi_option) {
if (comments) code += '// performs an arbitrary operation on some node\n'
code += 'template <typename Op>\n' +
'void modifyi(ptr n, int i, Op op) {\n' +
' if (!n) return;\n'
if (push) code += ' push(n);\n'
code += ' if (i == sz(n->l)) { n = merge(n->l, n->r); return; }\n' +
' if (i <= sz(n->l)) deli(n->l, i);\n' +
' else deli(n->r, i - 1 - sz(n->l));\n' +
' pull(n);\n' +
code += ' if (sz(n->l) == i) op(n);\n' +
' else if (i <= sz(n->l)) modifyi(n->l, i, op);\n' +
' else modifyi(n->r, i - 1 - sz(n->l), op);\n'
if (pull) code += ' pull(n);\n'
code += '}\n\n'
}

if (rot_option) {
if (comments) code += '// rotates treap such that index i is at the start\n'
code +='void rotate(ptr& n, int i) {\n' +
' auto [l, r] = spliti(n, i);\n' +
' n = merge(r, l);\n' +
'}\n\n'
}

if (partition_key) {
if (comments) code += "// finds smallest key such that pred returns false\n"
code += "template<typename Pred>\n" +
`${key_type} partition_key(ptr n, Pred pred) {\n`
if (push) code += " push(n);\n"
code += " if (pred(n)) return n->r ? partition_key(n->r, pred) : n->key + 1;\n" +
" else return n->l ? partition_key(n->l, pred) : n->key;\n" +
"}\n\n"
}

if (partition_index) {
if (comments) code += '// find smallest index such that pred returns false\n'
code += 'template<typename Pred>\n' +
'int partition_index(ptr n, Pred pred) {\n' +
' if (!n) return 0;\n'
if (push) code += ' push(n)\n'
code += ' if (pred(n)) return sz(n->l) + 1 + partition_index(n->r, pred);\n' +
' else return partition_index(n->l, pred);\n' +
'}\n\n'
}

if (cumulative_partition_key) {
if (comments) code += '// given a predicate that will return true for some prefix of aggregates,\n' +
'// find the key of the first prefix aggregate makes the predicate false (max key + 1 if always true)\n' +
'// eg. find the smallest prefix that has sum > x\n'
code += 'template <typename Pred>\n' +
`${key_type} cumulative_partition_key(ptr n, Pred pred, Value acc = vid) {\n`
if (push) code += ' push(n);\n'
code += ' if (!pred(acc + agg(n->l))) return n->l ? cumulative_partition_key(n->l, pred, acc) : n->key;\n' +
' if (!pred(acc = acc + agg(n->l) + n->val)) return n->key;\n' +
' return n->r ? cumulative_partition_key(n->r, pred, acc) : n->key + 1;\n' +
'}\n\n'
}

if (cumulative_partition_index) {
if (comments) code += '// given a predicate that will return true for some prefix of aggregates,\n' +
'// find the index of the first prefix aggregate that makes the predicate false (sz(n) if always true)\n' +
'// eg. find the smallest prefix that has sum > x\n'
code += 'template <typename Pred>\n' +
'int cumulative_partition_index(ptr n, Pred pred, Value acc = vid) {\n' +
' if (!n) return 0;\n'
if (push) code += ' push(n);\n'
code += ' if (!pred(acc + agg(n->l))) return cumulative_partition_index(n->l, pred, acc);\n' +
' if (!pred(acc = acc + agg(n->l) + n->val)) return sz(n->l);\n' +
' return sz(n->l) + 1 + cumulative_partition_index(n->r, pred, acc);\n' +
'}\n\n'
}

Expand Down

0 comments on commit 9a5ec8a

Please sign in to comment.