Submission #173188

#	Time	Username	Problem	Language	Result	Execution time	Memory
173188		mhy908	Rope (JOI17_rope)	C++14	100 / 100	2350 ms	58960 KiB

rope

#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define all(x) x.begin(), x.end()
using namespace std;
typedef long long LL;
typedef pair<int, int> pii;
typedef pair<LL, LL> pll;
const LL llinf=9000000000000000000;
const int inf=2000000000;
const LL hashnum=100000000;
int n, m;
int arr[1000010];
int cnt[1000010], cnt2[1000010];
vector<pii> q;
struct SEGMENT_TREE
{
    int initial=-inf;
    int x;
    struct NODE{
        int st, fin;
        int q;
    }tree[4000000];
    int f(int a, int b){return max(a, b);}
    void init(int point, int num){
        if(num==1)tree[point].st=tree[point].fin=++x;
        if(num<=1)return;
        init(point*2, num-num/2);
        init(point*2+1, num/2);
        tree[point].st=tree[point*2].st;
        tree[point].fin=tree[point*2+1].fin;
    }
    void cl(int point){
        tree[point].q=0;
        if(tree[point].st==tree[point].fin)return;
        cl(point*2);
        cl(point*2+1);
    }
    void update(int point, int num, int qu){
        if(tree[point].st==tree[point].fin){
            tree[point].q+=qu;
            return;
        }
        if(num<=tree[point*2].fin)update(point*2, num, qu);
        else update(point*2+1, num, qu);
        tree[point].q=f(tree[point*2].q, tree[point*2+1].q);
    }
    int query(int point, int a, int b){
        if(tree[point].st>=a&&tree[point].fin<=b)return tree[point].q;
        if(tree[point].st>b||tree[point].fin<a)return initial;
        return f(query(point*2, a, b), query(point*2+1, a, b));
    }
    void init(int num){init(1, num);}
    void update(int num, LL qu){update(1, num, qu);}
    void cl(){cl(1);}
    int query(int a, int b){return query(1, a, b);}
}seg;
int ans[1000010];
int main()
{
    scanf("%d %d", &n, &m);
    for(int i=1; i<=n; i++){
        scanf("%d", &arr[i]);
        if(i%2==0){
            if(arr[i-1]!=arr[i]){
                q.pb(mp(arr[i], arr[i-1]));
                q.pb(mp(arr[i-1], arr[i]));
                cnt[arr[i]]++;
                cnt[arr[i-1]]++;
            }
            else{
                cnt2[arr[i]]+=2;
            }
        }
        if(n%2&&i==n){
            cnt2[arr[i]]++;
        }
    }
    sort(all(q));
    seg.init(m);
    for(int i=1; i<=m; i++){
        seg.update(i, cnt[i]+cnt2[i]);
        ans[i]=inf;
    }
    int pv=0;
    for(int i=1; i<=m; i++){
        int temppv=pv;
        seg.update(i, -cnt[i]-cnt2[i]);
        for(; pv<q.size(); pv++){
            if(q[pv].F!=i)break;
            seg.update(q[pv].S, -1);
        }
        int turna=cnt[i];
        int turnb=n-cnt[i]*2-cnt2[i]-seg.query(1, m);
        ans[i]=min(ans[i], turna+turnb);
        seg.update(i, cnt[i]+cnt2[i]);
        for(; temppv<pv; temppv++){
            seg.update(q[temppv].S, 1);
        }
    }
    seg.cl();
    memset(cnt, 0, sizeof(cnt));
    memset(cnt2, 0, sizeof(cnt2));
    q.clear();
    for(int i=1; i<=n; i++){
        if(i==1){
            cnt2[arr[i]]++;
        }
        else if(i%2){
            if(arr[i-1]!=arr[i]){
                q.pb(mp(arr[i], arr[i-1]));
                q.pb(mp(arr[i-1], arr[i]));
                cnt[arr[i]]++;
                cnt[arr[i-1]]++;
            }
            else{
                cnt2[arr[i]]+=2;
            }
        }
        if(n%2==0&&i==n){
            cnt2[arr[i]]++;
        }
    }
    sort(all(q));
    for(int i=1; i<=m; i++)seg.update(i, cnt[i]+cnt2[i]);
    pv=0;
    for(int i=1; i<=m; i++){
        int temppv=pv;
        seg.update(i, -cnt[i]-cnt2[i]);
        for(; pv<q.size(); pv++){
            if(q[pv].F!=i)break;
            seg.update(q[pv].S, -1);
        }
        int turna=cnt[i];
        int turnb=n-cnt[i]*2-cnt2[i]-seg.query(1, m);
        ans[i]=min(ans[i], turna+turnb);
        seg.update(i, cnt[i]+cnt2[i]);
        for(; temppv<pv; temppv++){
            seg.update(q[temppv].S, 1);
        }
    }
    for(int i=1; i<=m; i++){
        printf("%d\n", ans[i]);
    }
}

Compilation message (stderr)

rope.cpp: In function 'int main()':
rope.cpp:91:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(; pv<q.size(); pv++){
               ~~^~~~~~~~~
rope.cpp:132:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(; pv<q.size(); pv++){
               ~~^~~~~~~~~
rope.cpp:63:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &n, &m);
     ~~~~~^~~~~~~~~~~~~~~~~
rope.cpp:65:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d", &arr[i]);
         ~~~~~^~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 30 / 30
• Subtask 3: 10 / 10
• Subtask 4: 25 / 25
• Subtask 5: 20 / 20