Submission #1119831

#	Time	Username	Problem	Language	Result	Execution time	Memory
1119831		Aviansh	Lasers (NOI19_lasers)	C++17	10 / 100	137 ms	262144 KiB

lasers

#include <bits/stdc++.h>

using namespace std;

struct node{
    int val;
    int left=-1;
    int right=-1;
};

class lazySparseSegTree{
    private:
        int cr = 1;
        int n;
        node *st;
        node *laz;
        node def;
        int no;
    public:
        lazySparseSegTree(int siz, int nodes){
            st = new node[nodes];
            laz = new node[nodes];
            def.val=0;
            def.left=-1;
            def.right=-1;
            fill(st,st+nodes,def);
            fill(laz,laz+nodes,def);
            n=siz-1;
            no=nodes;
        }

        void makeKids(int ind){
            if(st[ind].left==-1){
                st[ind].left=cr++;
                laz[ind].left=cr-1;
            }
            if(st[ind].right==-1){
                st[ind].right=cr++;
                laz[ind].right=cr-1;
            }
            assert(cr<no);
        }

        void pushdown(int ind, int l, int r){
            if(laz[ind].val==0){
                return;
            }
            if(l==r){
                st[ind].val=laz[ind].val*(r-l+1);
                return;
            }
            makeKids(ind);
            int mid = (l+r)/2;
            laz[laz[ind].left].val=laz[ind].val;
            laz[laz[ind].right].val=laz[ind].val;
            st[st[ind].left].val=laz[ind].val*(mid-l+1);
            st[st[ind].right].val=laz[ind].val*(r-mid);
            laz[ind].val=0;
        }

        void realUpdate(int l, int r, int s, int e, int val, int ind){
            if(r<s||l>e){
                return;
            }
            if(s<=l&&r<=e){
                laz[ind].val=val;
                st[ind].val=(r-l+1)*val;
                return;
            }
            int mid = (l+r)/2;
            pushdown(ind,l,r);
            makeKids(ind);
            realUpdate(l,mid,s,e,val,st[ind].left);
            realUpdate(mid+1,r,s,e,val,st[ind].right);
            st[ind].val=st[st[ind].left].val+st[st[ind].right].val;
        }
        void update(int l, int r, int val){
            realUpdate(0,n,l,r,val,0);
        }
        int realQuery(int l, int r, int s, int e, int ind){
            if(r<s||l>e){
                return 0;
            }
            pushdown(ind,l,r);
            if(s<=l&&r<=e){
                return st[ind].val;
            }
            int mid = (l+r)/2;
            makeKids(ind);
            return realQuery(l,mid,s,e,st[ind].left)+realQuery(mid+1,r,s,e,st[ind].right);
        }
        int query(int l, int r){
            return realQuery(0,n,l,r,0);
        }
};

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    int l,r;
    cin >> l >> r;
    vector<int>walls[r];
    lazySparseSegTree lsst(l,1e7);
    int sums[r];
    for(int i = 0;i<r;i++){
        int x;
        cin >> x;
        sums[i]=0;
        for(int j = 0;j<x;j++){
            int c;
            cin >> c;
            sums[i]+=c;
            walls[i].push_back(c);
        }
    }
    for(int i = 0;i<r;i++){
        int curl=0;
        for(int w : walls[i]){
            int lef = sums[i]-curl;
            lef=l-lef;
            int right = curl+w-1;
            if(right<lef){
                continue;
            }
            lsst.update(lef,right,1);
            curl+=w;
        }
    }
    cout << lsst.query(0,l-1);
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 0 / 20
• Subtask 4: 0 / 21
• Subtask 5: 0 / 22
• Subtask 6: 0 / 13