Submission #1243322

#	Time	Username	Problem	Language	Result	Execution time	Memory
1243322		nibert	Distributing Candies (IOI21_candies)	C++20	38 / 100	352 ms	27808 KiB

candies

#include <vector>
#include <algorithm>
using namespace std;

struct SegTree {
    struct Node {
        long long mn, mx;
        long long lazy;
    
        Node(long long _mn, long long _mx, long long _lazy) : mn(_mn), mx(_mx), lazy(_lazy) {}
    };
    int cap;
    vector<Node> tree;
     
    SegTree(int n, int _cap) : cap(_cap), tree(4 * n + 1, {0, 0, 0}) {}
      
    inline void apply(int pos, int val) {
        tree[pos].mn += val;
        tree[pos].mx += val;
        tree[pos].lazy += val;
    }
  
    inline void push(int pos) {
        long long val = tree[pos].lazy;
        if (val != 0) {
            apply(pos * 2 + 1, val);
            apply(pos * 2 + 2, val);
            tree[pos].lazy = 0;
        }
    }
    
    inline void merge(int pos) {
        int lChild = 2 * pos + 1, rChild = 2 * pos + 2;
        tree[pos].mn = min(tree[lChild].mn, tree[rChild].mn);
        tree[pos].mx = max(tree[lChild].mx, tree[rChild].mx);
    }
    
    inline void update(int tPos, int tLeft, int tRight, int l, int r, int val) {
        if (l > tRight || tLeft > r) {
            return;
        }
        if (l <= tLeft && tRight <= r) {
            apply(tPos, val);
            return;
        }
        push(tPos);
        int tMid = tLeft + (tRight - tLeft) / 2;
        update(tPos * 2 + 1, tLeft, tMid, l, min(tMid, r), val);
        update(tPos * 2 + 2, tMid + 1, tRight, max(l, tMid + 1), r, val);
        merge(tPos);
    }
    
    inline void fixLeftBound(int tPos, int tLeft, int tRight) {
        if (tree[tPos].mn >= 0) {
            return;
        }
        if (tree[tPos].mx < 0) {
            apply(tPos, -tree[tPos].mx);
        }
        if (tLeft == tRight) {
            return;
        }
        push(tPos);
        int tMid = tLeft + (tRight - tLeft) / 2;
        fixLeftBound(tPos * 2 + 1, tLeft, tMid);
        fixLeftBound(tPos * 2 + 2, tMid + 1, tRight);
        merge(tPos);
    }
    
    inline void fixRgihtBound(int tPos, int tLeft, int tRight) {
        if (tree[tPos].mx <= cap) {
            return;
        }
        if (tree[tPos].mn > cap) {
            apply(tPos, cap - tree[tPos].mn);
        }
        if (tLeft == tRight) {
            return;
        }
        push(tPos);
        int tMid = tLeft + (tRight - tLeft) / 2;
        fixRgihtBound(tPos * 2 + 1, tLeft, tMid);
        fixRgihtBound(tPos * 2 + 2, tMid + 1, tRight);
        merge(tPos);
    }
    
    inline int get(int tPos, int tLeft, int tRight, int pos) {
        if (tLeft == tRight) {
            return tree[tPos].mn;
        }
        push(tPos);
        int tMid = tLeft + (tRight - tLeft) / 2;
        if (pos <= tMid) {
            return get(tPos * 2 + 1, tLeft, tMid, pos);
        }
        return get(tPos * 2 + 2, tMid + 1, tRight, pos);
    }
};


vector<int> distribute_candies(vector<int> c,vector<int> l,vector<int> r,vector<int> v) {
    int n = c.size(), q = r.size();
    vector<long long> boxes(n, 0);
    bool isSubtask1 = (n <= 2000 && q <= 2000);
    bool isSubtask2 = true;
    for (int i = 0; i < q; ++i)
        if (v[i] <= 0) isSubtask2 = false;
    bool isSubtask3 = true;
    for (int i = 1; i < n; ++i)
        if (c[i] != c[0]) isSubtask3 = false;
    if(isSubtask1) {
        for (int i = 0; i < q; i++) {
            int left = l[i], right = r[i], value = v[i];
            if (value > 0) {
                for (int j = left; j <= right; j++) {
                    boxes[j] = min(1LL * c[j], boxes[j] + value);
                }
            } else {
                for (int j = left; j <= right; j++) {
                    boxes[j] = max(0ll, boxes[j] + value);
                }
            }
        }
        vector<int> result(n);
        for (int i=0; i < n; i ++){
            result[i] = boxes[i];
        }
        return result;
    } else if(isSubtask2) {
        for (int i = 0; i < q; i++){
            int left = l[i], right = r[i], value = v[i];
            boxes[left] += value;
            if (right + 1 < n) {
                boxes[right + 1] -= value;
            }
        }
        for (int i = 1; i < n; i++){
            boxes[i] += boxes[i - 1];
            boxes[i-1] = min(1LL * c[i-1], boxes[i - 1]);
        }
        boxes[n - 1] = min(1LL * c[n - 1], boxes[n - 1]);
        vector<int> result(n);
        for (int i=0; i < n; i ++){
            result[i] = boxes[i];
        }
        return result;
    } else if(isSubtask3) {
        SegTree segTree(n, c[0]);
        for (int i = 0; i < q; i++) {
            segTree.update(0, 0, n - 1, l[i], r[i], v[i]);
            segTree.fixLeftBound(0, 0, n - 1);
            segTree.fixRgihtBound(0, 0, n - 1);
       }
        vector<int> res(n);
        for (int i = 0; i < n; i++) {
        res[i] = segTree.get(0, 0, n - 1, i);
        }
    return res;
    }
}

Compilation message (stderr)

candies.cpp: In function 'std::vector<int> distribute_candies(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
candies.cpp:160:1: warning: control reaches end of non-void function [-Wreturn-type]
  160 | }
      | ^

• Subtask 1: 3 / 3
• Subtask 2: 8 / 8
• Subtask 3: 27 / 27
• Subtask 4: 0 / 29
• Subtask 5: 0 / 33