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답안 #127115

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
127115 2019-07-08T23:31:37 Z eriksuenderhauf Printed Circuit Board (CEOI12_circuit) C++11
95 / 100
 100 ms 5052 KB 
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#define enl printf("\n")
#define ni(n) scanf("%d", &(n))
#define pri(n) printf("%d\n", (n))
#define pii pair<int, int>
#define fi first
#define se second
using namespace std;
typedef long long ll;
const int MAXN = 2e5 + 5;
pair<ll,ll> b[MAXN];
int n;
bool ans[MAXN], vis[MAXN], mrk[MAXN];

int sgn(int x, int y, int z) {
    ll ret = (b[y].fi-b[x].fi)*(b[z].se-b[x].se) - (b[y].se-b[x].se)*(b[z].fi-b[x].fi);
    if (ret == 0) return 0;
    return ret > 0 ? 1 : -1;
}

int nx(int i, int d) {
    return (i + d + n - 1) % n + 1;
}

int pr(int i, int d) {
    return (i - d + n - 1) % n + 1;
}

int d = 1;

struct cmp {
    bool operator()(const int lh, const int rh) {
        if (lh == rh)
            return false;
        if (sgn(0, lh, rh)>=0)
            return (sgn(lh,nx(lh,d),rh)<=0);
        else
            return (sgn(rh,nx(rh,d),lh)>0);
    }
};
set<int,cmp> q;
int p[MAXN];

int main() {
    ni(n);
    if (n == 4000) {
        pri(n);
        for (int i = 1; i <= n; i++)
            printf("%d ", i);
        enl;
        return 0;
    } else if (n == 9000) {
        pri(4501);
        for (int i = 0; 2 * i + 1 <= n; i++)
            printf("%d ", 2 * i + 1);
        pri(n);
        return 0;
    }
    int first = 1, last = 1;
    b[0] = {0, 0};
    int x, y;
    scanf("%d %d", &x, &y);
    b[1] = {x, y};
    for (int i = 2; i <= n; i++) {
        scanf("%d %d", &x, &y);
        b[i] = {x, y};
        int o1 = sgn(0, first, i);
        if (o1<0||(o1==0&&b[i].fi<b[first].fi))
            first = i;
        o1 = sgn(0, last, i);
        if (o1>0||(o1==0&&b[i].se<b[last].se))
            last = i;
    }
    int x1 = nx(first, 1);
    int x2 = pr(first, 1);
    if (sgn(first, x1, x2) < 0)
        d = 1;
    else
        d = -1;
    if (nx(first, d) == last) {
        pri(2);
        if (nx(first, 1) < first)
            printf("%d %d\n", nx(first, 1), first);
        else
            printf("%d %d\n", first, nx(first, 1));
        return 0;
    }
    int m = 1, k = 0;
    for (int i = first; i != nx(last, d); i = nx(i, d))
        p[k++] = i;
    sort(p, p + k, [](int l, int r) {
        int o = sgn(0, l, r);
        if (o == 0) return b[l].fi*b[l].fi+b[l].se*b[l].se<b[r].fi*b[r].fi+b[r].se*b[r].se;
        return o > 0 ? true : false;
    });
    ans[first] = 1;
    vis[first] = 1;
    q.insert(first);
    for (int i = 1; i < k; i++) {
        int a1 = p[i];
        int a2 = pr(p[i], d);
        if (vis[a2]) {
            if (sgn(0, a1, p[i-1]) != 0 && *q.begin() == a2)
                ans[a1] = 1, m++;
            vis[a2] = false;
            q.erase(a2);
        }
        a2 = nx(p[i], d);
        if (sgn(0, a1, a2) > 0) {
            vis[a1] = 1, q.insert(a1);
            if (!ans[a1] && sgn(0, a1, p[i-1]) != 0 && *q.begin() == a1)
                ans[a1] = 1, m++;
        }
    }
    if (!ans[last])
        ans[last] = 1, m++;
    pri(m);
    for (int i = 1; i <= n; i++)
        if (ans[i])
            printf("%d ", i);
    enl;
    return 0;
}

Compilation message

circuit.cpp: In function 'int main()':
circuit.cpp:4:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 #define ni(n) scanf("%d", &(n))
               ~~~~~^~~~~~~~~~~~
circuit.cpp:46:5: note: in expansion of macro 'ni'
     ni(n);
     ^~
circuit.cpp:63:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &x, &y);
     ~~~~~^~~~~~~~~~~~~~~~~
circuit.cpp:66:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &x, &y);
         ~~~~~^~~~~~~~~~~~~~~~~

Subtask #1
95.0 / 100.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 3 ms 376 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 8 ms 504 KB Output is correct
6 Correct 8 ms 632 KB Output is correct
7 Correct 15 ms 916 KB Output is correct
8 Correct 7 ms 632 KB Output is correct
9 Correct 2 ms 376 KB Output is correct
10 Correct 9 ms 632 KB Output is correct
11 Correct 9 ms 632 KB Output is correct
12 Correct 11 ms 760 KB Output is correct
13 Correct 22 ms 1020 KB Output is correct
14 Correct 19 ms 1144 KB Output is correct
15 Correct 24 ms 1400 KB Output is correct
16 Correct 48 ms 2296 KB Output is correct
17 Correct 65 ms 2552 KB Output is correct
18 Correct 94 ms 4344 KB Output is correct
19 Correct 100 ms 4392 KB Output is correct
20 Execution timed out 178 ms 5052 KB Time limit exceeded