# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
1007664 |
2024-06-25T09:55:30 Z |
farrellw |
Wall (IOI14_wall) |
C++14 |
|
0 ms |
0 KB |
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define INF 100005
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
#include "wall.h"
ii combine(ii upd_new, ii upd_old) { // apply upd_new to upd_old
ii res = {max(upd_new.fi, upd_old.fi), min(upd_new.se, upd_old.se)};
if (res.fi > res.se) { // The ranges are disjoint, so suffices to check either
return (upd_old.se < upd_new.se) ? make_pair(upd_new.fi, upd_new.fi) : make_pair(upd_new.se, upd_new.se);
}
return res;
}
struct Segtree { // Segtree of updates
int sz;
vector<ii> upd; // store (a, b)
vi left;
vi right;
vi mid;
Segtree(int N) {
sz = 1;
while (sz < N)
sz *= 2;
upd = vii(2 * sz, {0, INF});
left = vi(2 * sz, 0);
right = vi(2 * sz, 0);
mid = vi(2 * sz, 0);
for(int id = sz-1; id < 2*sz-1; id++) {
left[id] = id-sz+1;
right[id] = id-sz+2;
}
for(int id = sz-2; id >= 0; id--) {
left[id] = left[(id<<1)|1];
right[id] = right[2 * id + 2];
mid[id] = (left[id] + right[id])>>1;
}
}
void push(int id, int left, int right) { // O(1), for regular updates
if (right[id] - left[id] == 1)
return;
upd[(id<<1)|1] = combine(upd[id], upd[(id<<1)|1]);
upd[2 * id + 2] = combine(upd[id], upd[2 * id + 2]);
upd[id] = {0, INF};
}
void push_recursive(int id, int left, int right) { // O(N), only for answer extraction at the end
if(right - left == 1)
return;
push(id, left, right);
int mid = (left + right)>>1;
push_recursive((id<<1)|1, left, mid);
push_recursive(2 * id + 2, mid, right);
}
void range_upd(int qleft, int qright, ii val, int id, int left, int right) {
if (qleft <= left && right <= qright) {
upd[id] = combine(val, upd[id]);
return;
}
if (qright <= left || right <= qleft)
return;
push(id, left, right);
int mid = (left + right)>>1;
range_upd(qleft, qright, val, (id<<1)|1, left, mid);
range_upd(qleft, qright, val, 2 * id + 2, mid, right);
}
void range_upd(int qleft, int qright, ii val) {
range_upd(qleft, qright, val, 0, 0, sz);
}
};
void buildWall(int n, int k, int op[], int left[], int right[], int height[], int finalHeight[]) {
Segtree tree(n);
for(int z = 0; z < k; z++) {
ii upd_val = (op[z] == 1) ? make_pair(height[z], INF) : make_pair(0, height[z]);
tree.range_upd(left[z], right[z]+1, upd_val);
}
tree.push_recursive(0, 0, tree.sz);
for(int z = 0; z < n; z++) {
finalHeight[z] = tree.upd[z+tree.sz-1].fi;
}
return;
}
Compilation message
wall.cpp: In member function 'void Segtree::push(int, int, int)':
wall.cpp:45:18: error: invalid types 'int[int]' for array subscript
45 | if (right[id] - left[id] == 1)
| ^
wall.cpp:45:29: error: invalid types 'int[int]' for array subscript
45 | if (right[id] - left[id] == 1)
| ^