oj.uz

Submission #855540

# Submission time Handle Problem Language Result Execution time Memory
855540 2023-10-01T11:56:59 Z hariaakas646 Event Hopping (BOI22_events) C++17
30 / 100
 283 ms 19308 KB 
#include <bits/stdc++.h>

using namespace std;

#define scd(t) scanf("%d", &t)
#define sclld(t) scanf("%lld", &t)
#define forr(i, j, k) for (int i = j; i < k; i++)
#define frange(i, j) forr(i, 0, j)
#define all(cont) cont.begin(), cont.end()
#define mp make_pair
#define pb push_back
#define f first
#define s second
typedef long long int lli;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<lli> vll;
typedef vector<string> vs;
typedef vector<pii> vii;
typedef vector<vi> vvi;
typedef map<int, int> mpii;
typedef set<int> seti;
typedef multiset<int> mseti;
typedef long double ld;


void usaco()
{
    freopen("/media/hariaakash646/785EF1075EF0BF46/CompetitiveProgramming/input.in", "r", stdin);
//    freopen("problem.out", "w", stdout);
}

int n, q1;
vector<pair<pii, int>> dur, dur1;

vvi lift;

int binlift(int x, int c) {
    frange(i, 20) {
        if(c & (1<<i)) {
            x = lift[i][x];
        }
    }
    return x;
}

int main() {
    // usaco();
    scd(n);
    scd(q1);
    dur = vector<pair<pii, int>>(n);
    map<int, int> mv;
    frange(i, n) {
        scd(dur[i].f.s);
        scd(dur[i].f.f);
        dur[i].s = i+1;
        if(mv.find(dur[i].f.f) == mv.end()) {
            mv[dur[i].f.f] = dur[i].f.s;
        }
        else {
            mv[dur[i].f.f] = min(mv[dur[i].f.f], dur[i].f.s);
        }
    }

    dur1 = vector<pair<pii, int>>(n+1);
    forr(i, 1, n+1) {
        dur1[i] = dur[i-1];
    }
    sort(all(dur), greater<>());

    lift = vvi(20, vi(n+1));

    deque<pii> q;

    for(auto p : dur) {
        while(q.size() && q.front().f > p.f.f) {
            q.pop_front();
        }
        if(q.size()) {
            lift[0][p.s] = q.front().s;
        }
        else lift[0][p.s] = p.s;
        if(!q.size()) q.push_back(mp(p.f.s, p.s));
        else if(p.f.s < q.back().f) q.push_back(mp(p.f.s, p.s));
    }

    forr(i, 1, 20) {
        forr(j, 1, n+1) {
            lift[i][j] = lift[i-1][lift[i-1][j]];
        }
    }

    frange(_, q1) {
        int u, v;
        scd(u);
        scd(v);

        if(dur1[u].f.f > dur1[v].f.f) {
            printf("impossible\n");
            continue;
        }
        else if(u == v) {printf("0\n"); continue;}

        int lo = 0;
        int hi = n;

        while(lo != hi) {
            int mid = (lo + hi)/2;
            int x = binlift(u, mid);
            if(dur1[x].f.f >= dur1[v].f.f) {
                hi = mid;
            }
            else {
                lo = mid+1;
            }
        }
        int x = binlift(u, lo);
        if(x == v) {
            printf("%d\n", lo);
            continue;
        }
        if(lo == 0) {
            printf("1\n");
            continue;
        }
        lo--;
        x = binlift(u, lo);
        if(dur1[v].f.s <= dur1[x].f.f) {
            printf("%d\n", lo+1);
        }
        else if(mv[dur1[v].f.f] <= dur1[x].f.f) {
            printf("%d\n", lo+2);
        }
        else {
            printf("impossible\n");
        }

    }


}

Compilation message

events.cpp: In function 'void usaco()':
events.cpp:30:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     freopen("/media/hariaakash646/785EF1075EF0BF46/CompetitiveProgramming/input.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
events.cpp: In function 'int main()':
events.cpp:5:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | #define scd(t) scanf("%d", &t)
      |                ~~~~~^~~~~~~~~~
events.cpp:50:5: note: in expansion of macro 'scd'
   50 |     scd(n);
      |     ^~~
events.cpp:5:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | #define scd(t) scanf("%d", &t)
      |                ~~~~~^~~~~~~~~~
events.cpp:51:5: note: in expansion of macro 'scd'
   51 |     scd(q1);
      |     ^~~
events.cpp:5:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | #define scd(t) scanf("%d", &t)
      |                ~~~~~^~~~~~~~~~
events.cpp:55:9: note: in expansion of macro 'scd'
   55 |         scd(dur[i].f.s);
      |         ^~~
events.cpp:5:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | #define scd(t) scanf("%d", &t)
      |                ~~~~~^~~~~~~~~~
events.cpp:56:9: note: in expansion of macro 'scd'
   56 |         scd(dur[i].f.f);
      |         ^~~
events.cpp:5:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | #define scd(t) scanf("%d", &t)
      |                ~~~~~^~~~~~~~~~
events.cpp:96:9: note: in expansion of macro 'scd'
   96 |         scd(u);
      |         ^~~
events.cpp:5:21: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 | #define scd(t) scanf("%d", &t)
      |                ~~~~~^~~~~~~~~~
events.cpp:97:9: note: in expansion of macro 'scd'
   97 |         scd(v);
      |         ^~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 144 ms 18076 KB Output is correct
3 Correct 183 ms 18024 KB Output is correct
4 Correct 203 ms 17972 KB Output is correct
5 Correct 191 ms 18120 KB Output is correct
6 Correct 180 ms 18796 KB Output is correct
7 Correct 176 ms 18788 KB Output is correct
8 Correct 135 ms 19148 KB Output is correct
9 Correct 155 ms 19308 KB Output is correct
10 Correct 283 ms 18884 KB Output is correct
11 Correct 173 ms 19004 KB Output is correct
12 Correct 122 ms 16256 KB Output is correct

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 604 KB Output is correct
4 Correct 1 ms 604 KB Output is correct
5 Incorrect 1 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 604 KB Output is correct
4 Correct 1 ms 604 KB Output is correct
5 Incorrect 1 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #4
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 604 KB Output is correct
4 Correct 1 ms 604 KB Output is correct
5 Incorrect 1 ms 348 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 144 ms 18072 KB Output is correct
2 Correct 178 ms 18032 KB Output is correct
3 Correct 190 ms 18124 KB Output is correct
4 Correct 159 ms 18644 KB Output is correct
5 Correct 178 ms 18428 KB Output is correct
6 Correct 156 ms 18208 KB Output is correct
7 Correct 140 ms 18220 KB Output is correct
8 Correct 147 ms 18376 KB Output is correct
9 Correct 72 ms 17616 KB Output is correct
10 Correct 165 ms 17992 KB Output is correct
11 Correct 137 ms 17868 KB Output is correct
12 Correct 169 ms 17960 KB Output is correct

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 144 ms 18076 KB Output is correct
3 Correct 183 ms 18024 KB Output is correct
4 Correct 203 ms 17972 KB Output is correct
5 Correct 191 ms 18120 KB Output is correct
6 Correct 180 ms 18796 KB Output is correct
7 Correct 176 ms 18788 KB Output is correct
8 Correct 135 ms 19148 KB Output is correct
9 Correct 155 ms 19308 KB Output is correct
10 Correct 283 ms 18884 KB Output is correct
11 Correct 173 ms 19004 KB Output is correct
12 Correct 122 ms 16256 KB Output is correct
13 Correct 0 ms 344 KB Output is correct
14 Correct 0 ms 344 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 1 ms 604 KB Output is correct
17 Incorrect 1 ms 348 KB Output isn't correct
18 Halted 0 ms 0 KB -