Submission #127123

# Submission time Handle Problem Language Result Execution time Memory
127123 2019-07-09T00:01:34 Z eriksuenderhauf Printed Circuit Board (CEOI12_circuit) C++11
90 / 100
100 ms 3676 KB
#pragma GCC optimize("O3")
#pragma GCC target ("sse4")
#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 pb push_back
#define fi first
#define se second
using namespace std;
typedef long long ll;
const int MAXN = 2e5 + 5;
pair<int,int> b[MAXN];
int n;
bool ans[MAXN], vis[MAXN], mrk[MAXN];

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

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

inline 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);
        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].se<b[r].fi+b[r].se;
        return o > 0 ? true : false;
    });
    vector<int> ans2;
    ans[first] = 1;
    ans2.pb(first);
    vis[first] = 1;
    q.insert(first);
    for (int i = 1; i < k; i++) {
        int a1 = p[i], a2 = pr(p[i], d);
        if (vis[a2]) {
            if (sgn(0, a1, p[i-1]) != 0 && *q.begin() == a2)
                ans[a1] = 1, ans2.pb(a1);
            vis[a2] = false;
            q.erase(a2);
        }
        if (sgn(0, a1, nx(p[i], d)) > 0) {
            vis[a1] = 1, q.insert(a1);
            if (!ans[a1] && sgn(0, a1, p[i-1]) != 0 && *q.begin() == a1)
                ans[a1] = 1, ans2.pb(a1);
        }
    }
    if (!ans[last]) ans[last] = 1, ans2.pb(last);
    sort(ans2.begin(), ans2.end());
    pri(ans2.size());
    for (int i: ans2)
        printf("%d ", i);
    printf("\n");
    return 0;
}

Compilation message

circuit.cpp: In function 'int main()':
circuit.cpp:6:34: warning: format '%d' expects argument of type 'int', but argument 2 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=]
 #define pri(n) printf("%d\n", (n))
                               ~~~^
circuit.cpp:119:5: note: in expansion of macro 'pri'
     pri(ans2.size());
     ^~~
circuit.cpp:90:9: warning: unused variable 'm' [-Wunused-variable]
     int m = 1, k = 0;
         ^
circuit.cpp:5:20: 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:47:5: note: in expansion of macro 'ni'
     ni(n);
     ^~
circuit.cpp:64:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &x, &y);
     ~~~~~^~~~~~~~~~~~~~~~~
circuit.cpp:67:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &x, &y);
         ~~~~~^~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 3 ms 504 KB Output is correct
4 Correct 2 ms 376 KB Output is correct
5 Correct 8 ms 632 KB Output is correct
6 Correct 8 ms 632 KB Output is correct
7 Correct 16 ms 764 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 10 ms 632 KB Output is correct
12 Correct 12 ms 760 KB Output is correct
13 Correct 22 ms 1016 KB Output is correct
14 Correct 19 ms 888 KB Output is correct
15 Correct 24 ms 1016 KB Output is correct
16 Correct 47 ms 1656 KB Output is correct
17 Correct 65 ms 2168 KB Output is correct
18 Correct 93 ms 2812 KB Output is correct
19 Execution timed out 101 ms 2988 KB Time limit exceeded
20 Execution timed out 174 ms 3676 KB Time limit exceeded