Submission #1045384

#	Time	Username	Problem	Language	Result	Execution time	Memory
1045384		Uasoni	Pyramid Base (IOI08_pyramid_base)	C++14	80 / 100	5069 ms	38320 KiB

pyramid_base

#include<bits/stdc++.h>
using namespace std;

const int maxn = 4e5+5, maxp = 1e6+5, inf = 1e9;
int n, m, p, b;
struct R {
    int x1, y1, x2, y2, c;
    R() { x1 = y1 = x2 = y2 = c = 0; }
} obs[maxn];

struct N {
    int v, l;
} stree[4*maxp];
void push(int i) {
    if(stree[i].l != 0) {
        stree[i<<1].v += stree[i].l; stree[i<<1|1].v += stree[i].l;
        stree[i<<1].l += stree[i].l; stree[i<<1|1].l += stree[i].l;
        stree[i].l = 0;
    }
}
void update(int lq, int rq, int val, int i = 1, int l = 1, int r = maxp) {
    if(lq <= l && r <= rq) {
        stree[i].v += val, stree[i].l += val;
        return;
    }
    push(i);
    int mid = (l+r)/2;
    if(lq <= mid) update(lq, rq, val, i<<1, l, mid);
    if(rq >= mid+1) update(lq, rq, val, i<<1|1, mid+1, r);
    stree[i].v = min(stree[i<<1].v, stree[i<<1|1].v);
}
int query(int lq, int rq, int i = 1, int l = 1, int r = maxp) {
    if(lq <= l && r <= rq) return stree[i].v;
    push(i);
    int mid = (l+r)/2, ret = inf;
    if(lq <= mid) ret = min(ret, query(lq, rq, i<<1, l, mid));
    if(rq >= mid+1) ret = min(ret, query(lq, rq, i<<1|1, mid+1, r));
    return ret;
}

struct E {
    int t, val, l, r;
    bool operator<(const E &o) const {
        return t < o.t;
    }
}; vector<E> evs;

bool check(int x) {
    bool ret = false;
    evs.clear();
    for(int i = 1; i <= p; i++) {
        evs.push_back({max(1, obs[i].x1-x+1), obs[i].c, max(1, obs[i].y1-x+1), obs[i].y2});
        evs.push_back({obs[i].x2+1, -obs[i].c, max(1, obs[i].y1-x+1), obs[i].y2});
    }
    sort(evs.begin(), evs.end());
    for(int i = 0; i < evs.size(); i++) {
        update(evs[i].l, evs[i].r, evs[i].val);
        if(i >= evs.size()-1 || evs[i].t != evs[i+1].t) {
            if(evs[i].t+x-1 <= m) ret |= (query(1, n-x+1) <= b);
        }
    }
    return ret;
}

int bsearch(int l, int r) {
    int ret = 0;
    while(l <= r) {
        int mid = (l+r)/2;
        if(check(mid)) l = mid+1, ret = mid;
        else r = mid-1;
    }
    return ret;
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> m >> n >> b >> p; // m columns, n rows
    for(int i = 1; i <= p; i++) cin >> obs[i].x1 >> obs[i].y1 >> obs[i].x2 >> obs[i].y2 >> obs[i].c;
    cout << bsearch(1, min(m, n)) << "\n";
}

Compilation message (stderr)

pyramid_base.cpp: In function 'bool check(int)':
pyramid_base.cpp:56:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<E>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |     for(int i = 0; i < evs.size(); i++) {
      |                    ~~^~~~~~~~~~~~
pyramid_base.cpp:58:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<E>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |         if(i >= evs.size()-1 || evs[i].t != evs[i+1].t) {
      |            ~~^~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 7 / 7
• Subtask 9: 7 / 7
• Subtask 10: 7 / 7
• Subtask 11: 7 / 7
• Subtask 12: 7 / 7
• Subtask 13: 10 / 10
• Subtask 14: 0 / 10
• Subtask 15: 0 / 10