Submission #386759

#	Time	Username	Problem	Language	Result	Execution time	Memory
386759		wenqi	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	10 / 100	1097 ms	38776 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

using ll = long long;

#define all(x) begin(x), end(x)
#define fillc(p, t, v) fill_n((t*) p, sizeof(p) / sizeof(t), v)
#define pb push_back

#define MID 2069
#define O 2069
#define MAX 96900000000ll
#define K 9999999999699ll
#define OM (O / MID + 69)

int N, M;

int B[O];
int P[O];
int TP;

vector<int> SMALL[O];
vector<int> BIG[O];

ll smallc[O][MID + 69];
bool seen1[O][MID + 69];
ll bigc[O][2 * OM + 69];

ll dp_small(int, int);
ll dp_big(int, int);

ll dp_small(int pos, int step) {
    ll& ans = smallc[pos][step];
    if(ans != -2) return ans;
    ans = K;
    ll a = ans;
    if(pos == TP) return ans = 0;
    for(int j : SMALL[pos]) {
        a = min(a, dp_small(B[j], P[j]));
    }
    for(int j : BIG[pos]) {
        a = min(a, dp_big(j, OM));
    }
    if(pos - step >= 0) {
        a = min(a, 1 + dp_small(pos - step, step));
    }
    if(pos + step < N) {
        a = min(a, 1 + dp_small(pos + step, step));
    }
    if(a == K) {
        ans = -2;
        return K;
    }else{
        ans = min(ans, MAX);
        return ans = a;
    }
}

ll dp_big(int i, int offset) {
    ll& ans = bigc[i][offset];
    if(ans != -2) return ans;
    ans = MAX;
    int pos = B[i] + (offset - OM) * P[i];
    if(pos == TP) return ans = 0;
    for(int j : SMALL[pos]) {
        ans = min(ans, dp_small(B[j], P[j]));
    }
    for(int j : BIG[pos]) {
        ans = min(ans, dp_big(j, OM));
    }
    if(pos - P[i] >= 0) {
        ans = min(ans, 1 + dp_big(i, offset - 1));
    }
    if(pos + P[i] < N) {
        ans = min(ans, 1 + dp_big(i, offset + 1));
    }
    return ans;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cin >> N >> M;
    for(int i = 0; i < M; i++) {
        cin >> B[i] >> P[i];
        if(P[i] < MID)
            SMALL[B[i]].pb(i);
        else
            BIG[B[i]].pb(i);
        if(i == 1) TP = B[i];
    }
    fillc(smallc, ll, -2);
    fillc(bigc, ll, -2);
    ll ans;
    if(P[0] < MID) {
        ans = dp_small(B[0], P[0]);
    }else{
        ans = dp_big(0, OM);
    }
    cout << (ans >= MAX ? -1 : ans) << '\n';
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 12
• Subtask 3: 0 / 14
• Subtask 4: 0 / 21
• Subtask 5: 0 / 43