oj.uz

Submission #94587

# Submission time Handle Problem Language Result Execution time Memory
94587 2019-01-21T11:26:57 Z FutymyClone Global Warming (NOI13_gw) C++14
40 / 40
 307 ms 15992 KB 
#include <bits/stdc++.h>

using namespace std;

const int N = 1e6 + 5;

int n, res = 0, ans = 0;
pair <int, int> a[N];

struct disj {
    int par[N];
    bool mark[N];
    void init (int n) {
        iota(par + 1, par + n + 1, 1);
        memset(mark, 0, sizeof(mark));
    }

    int Find (int x) {
        return par[x] == x ? x : par[x] = Find(par[x]);
    }

    void join (int x, int y) {
        x = Find(x); y = Find(y);
        if (x == y) return;
        par[y] = x;
        mark[x] |= mark[y];
    }
} dsu;

int main(){
    scanf("%d", &n);
    for (int i = 1; i <= n; i++) scanf("%d", &a[i].first), a[i].second = i;
    sort(a + 1, a + n + 1, greater <pair <int, int> >());

    int ptr = 1;
    dsu.init(n);
    for (int i = 1; i <= n; i = ptr) {
        while (ptr <= n && a[ptr].first == a[i].first) {
            if (a[ptr].second == n) {
                if (dsu.mark[dsu.Find(a[ptr].second - 1)]) dsu.join(a[ptr].second, a[ptr].second - 1);
                else res++, dsu.mark[a[ptr].second] = true;
            }
            else if (a[ptr].second == 1) {
                if (dsu.mark[dsu.Find(a[ptr].second + 1)]) dsu.join(a[ptr].second, a[ptr].second + 1);
                else res++, dsu.mark[a[ptr].second] = true;
            }
            else {
                if (dsu.mark[dsu.Find(a[ptr].second - 1)]) {
                    if (dsu.mark[dsu.Find(a[ptr].second + 1)]) {
                        dsu.join(a[ptr].second, a[ptr].second - 1);
                        dsu.join(a[ptr].second, a[ptr].second + 1);
                        res--;
                    }
                    else dsu.join(a[ptr].second, a[ptr].second - 1);
                }
                else {
                    if (dsu.mark[dsu.Find(a[ptr].second + 1)]) dsu.join(a[ptr].second, a[ptr].second + 1);
                    else res++, dsu.mark[a[ptr].second] = true;
                }
            }

            ptr++;
        }

        ans = max(ans, res);
    }

    printf("%d", ans);
    return 0;
}

Compilation message

gw.cpp: In function 'int main()':
gw.cpp:31:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
gw.cpp:32:58: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for (int i = 1; i <= n; i++) scanf("%d", &a[i].first), a[i].second = i;
                                  ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 1272 KB Output is correct
2 Correct 3 ms 1272 KB Output is correct
3 Correct 3 ms 1268 KB Output is correct
4 Correct 3 ms 1272 KB Output is correct
5 Correct 3 ms 1400 KB Output is correct

Subtask #2
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 2780 KB Output is correct
2 Correct 23 ms 2936 KB Output is correct
3 Correct 23 ms 2808 KB Output is correct
4 Correct 23 ms 2680 KB Output is correct
5 Correct 23 ms 2808 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 3392 KB Output is correct
2 Correct 18 ms 3064 KB Output is correct
3 Correct 28 ms 3320 KB Output is correct
4 Correct 28 ms 3320 KB Output is correct
5 Correct 27 ms 3192 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 307 ms 13432 KB Output is correct
2 Correct 274 ms 13304 KB Output is correct
3 Correct 280 ms 13384 KB Output is correct
4 Correct 281 ms 13304 KB Output is correct
5 Correct 275 ms 13292 KB Output is correct

Subtask #5
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 294 ms 13460 KB Output is correct
2 Correct 286 ms 13432 KB Output is correct
3 Correct 292 ms 13432 KB Output is correct
4 Correct 238 ms 13816 KB Output is correct
5 Correct 233 ms 15992 KB Output is correct