제출 #605514

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
605514		duality	Event Hopping (BOI22_events)	C++17	0 / 100	816 ms	20660 KiB

events

#define DEBUG 0

#include <bits/stdc++.h>
using namespace std;

#if DEBUG
// basic debugging macros
int __i__,__j__;
#define printLine(l) for(__i__=0;__i__<l;__i__++){cout<<"-";}cout<<endl
#define printLine2(l,c) for(__i__=0;__i__<l;__i__++){cout<<c;}cout<<endl
#define printVar(n) cout<<#n<<": "<<n<<endl
#define printArr(a,l) cout<<#a<<": ";for(__i__=0;__i__<l;__i__++){cout<<a[__i__]<<" ";}cout<<endl
#define print2dArr(a,r,c) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<a[__i__][__j__]<<" ";}cout<<endl;}
#define print2dArr2(a,r,c,l) cout<<#a<<":\n";for(__i__=0;__i__<r;__i__++){for(__j__=0;__j__<c;__j__++){cout<<setw(l)<<setfill(' ')<<a[__i__][__j__]<<" ";}cout<<endl;}

// advanced debugging class
// debug 1,2,'A',"test";
class _Debug {
    public:
        template<typename T>
        _Debug& operator,(T val) {
            cout << val << endl;
            return *this;
        }
};
#define debug _Debug(),
#else
#define printLine(l)
#define printLine2(l,c)
#define printVar(n)
#define printArr(a,l)
#define print2dArr(a,r,c)
#define print2dArr2(a,r,c,l)
#define debug
#endif

// define
#define MAX_VAL 999999999
#define MAX_VAL_2 999999999999999999LL
#define EPS 1e-6
#define mp make_pair
#define pb push_back

// typedef
typedef unsigned int UI;
typedef long long int LLI;
typedef unsigned long long int ULLI;
typedef unsigned short int US;
typedef pair<int,int> pii;
typedef pair<LLI,LLI> plli;
typedef vector<int> vi;
typedef vector<LLI> vlli;
typedef vector<pii> vpii;
typedef vector<plli> vplli;

// ---------- END OF TEMPLATE ----------

int S[100000],E[100000];
vi all;
vpii qq[100000];
int order[100000],ans[100000];
int parent[200000],out[200000],outnum[200000],mm[200000];
int B;
int rebuild(int b) {
    int i;
    if (mm[b] == 1e9) {
        for (i = b*B; i < min((b+1)*B,(int) all.size()); i++) {
            if (parent[i] >= i) out[i] = 1e9;
            else if (parent[i] < b*B) out[i] = parent[i],outnum[i] = 1;
            else out[i] = out[parent[i]],outnum[i] = outnum[parent[i]]+1;
        }
    }
    return 0;
}
int main() {
    int i;
    int N,Q,s,e;
    scanf("%d %d",&N,&Q);
    for (i = 0; i < N; i++) scanf("%d %d",&S[i],&E[i]),all.pb(S[i]),all.pb(E[i]);
    for (i = 0; i < Q; i++) {
        scanf("%d %d",&s,&e),s--,e--;
        qq[e].pb(mp(s,i));
    }
    sort(all.begin(),all.end());
    all.resize(unique(all.begin(),all.end())-all.begin());
    for (i = 0; i < N; i++) {
        S[i] = lower_bound(all.begin(),all.end(),S[i])-all.begin();
        E[i] = lower_bound(all.begin(),all.end(),E[i])-all.begin();
        order[i] = i;
    }
    sort(order,order+N,[&](int a,int b) { return E[a] < E[b]; });

    int j,k;
    B = sqrt(all.size());
    for (i = 0; i < all.size(); i++) parent[i] = mm[i] = out[i] = 1e9;
    for (i = 0; i < N; i++) {
        int u = order[i];
        if (S[u]/B == E[u]/B) {
            for (j = S[u]; j <= E[u]; j++) parent[j] = min(parent[j],S[u]);
            rebuild(S[u]/B);
        }
        else {
            for (j = S[u]; j < (S[u]/B+1)*B; j++) parent[j] = min(parent[j],S[u]);
            for (j = S[u]/B+1; j < E[u]/B; j++) {
                if (j == S[u]/B+1) {
                    for (k = j*B; k < (j+1)*B; k++) parent[k] = min(parent[k],S[u]);
                    rebuild(j);
                }
                else mm[j] = min(mm[j],S[u]);
            }
            for (j = (E[u]/B)*B; j <= E[u]; j++) parent[j] = min(parent[j],S[u]);
            rebuild(S[u]/B),rebuild(E[u]/B);
        }
        for (auto [s,j]: qq[u]) {
            if (s == u) ans[j] = 0;
            else if (E[s] > E[u]) ans[j] = -1;
            else {
                int v = S[u];
                ans[j] = 1;
                while (v > E[s]) {
                    if ((v-E[s] < 2*B+5) || (mm[v/B] != 1e9)) {
                        if (min(mm[v/B],parent[v]) >= v) {
                            ans[j] = -1;
                            break;
                        }
                        else v = min(mm[v/B],parent[v]),ans[j]++;
                    }
                    else ans[j] += outnum[v],v = out[v];
                }
            }
        }
    }
    for (i = 0; i < Q; i++) {
        if (ans[i] == -1) printf("impossible\n");
        else printf("%d\n",ans[i]);
    }

    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

events.cpp: In function 'int main()':
events.cpp:95:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   95 |     for (i = 0; i < all.size(); i++) parent[i] = mm[i] = out[i] = 1e9;
      |                 ~~^~~~~~~~~~~~
events.cpp:78:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   78 |     scanf("%d %d",&N,&Q);
      |     ~~~~~^~~~~~~~~~~~~~~
events.cpp:79:34: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |     for (i = 0; i < N; i++) scanf("%d %d",&S[i],&E[i]),all.pb(S[i]),all.pb(E[i]);
      |                             ~~~~~^~~~~~~~~~~~~~~~~~~~~
events.cpp:81:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   81 |         scanf("%d %d",&s,&e),s--,e--;
      |         ~~~~~^~~~~~~~~~~~~~~

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• Subtask 6: 0 / 30