Submission #696523

#	Time	Username	Problem	Language	Result	Execution time	Memory
696523		sharaelong	Mechanical Doll (IOI18_doll)	C++17	2 / 100	42 ms	8428 KiB

doll

#include "doll.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;

int rev(int x, int sz) {
    int k = 31 - __builtin_clz(sz);
    int ret = 0;
    for (int i=0; i<k; ++i) ret |= (1 << (k-1-i)) * ((x & (1 << i)) > 0);
    // cout << x << ' ' << sz << ' ' << ret << endl;
    return ret;
}

int switch_cnt = 0;
vector<int> c, x, y;

int build_single_circuit(vector<int> A) {
    int root = -switch_cnt-1;
    int n = A.size();
    int offset = 0;
    // cout << n << endl;
    // for (int i: A) cout << i << ' ';
    // cout << endl;
    while (offset < n) {
        int sz = 1 << (31 - __builtin_clz(n-offset));
        // cout << switch_cnt << ' ' << n << ' ' << sz << ' ' << offset << endl;
        for (int i=1; i<sz/2; ++i) {
            x.push_back(-(switch_cnt + 2*i));
            y.push_back(-(switch_cnt + 2*i+1));
        }
        for (int i=0; i<sz/2; ++i) {
            x.push_back(A[offset + rev(2*i, sz)]);
            // c[offset + rev(2*i, sz)] = -switch_cnt-1;
            if (i+1 < sz/2) {
                y.push_back(A[offset + rev(2*i+1, sz)]);
                // c[offset + rev(2*i+1, sz)] = -switch_cnt-1;
            }
        }
        if (n-offset == sz) {
            y.push_back(A.back());
            break;
        } else {
            switch_cnt += sz-1;
            offset += sz-1;
            y.push_back(-switch_cnt-1);
        }
    }
    return root;
}

void create_circuit(int m, vector<int> A) {
    vector<vector<int>> go(m+1);
    for (int i=0; i+1<A.size(); ++i) go[A[i]].push_back(A[i+1]);
    go[A.back()].push_back(0);

    c.resize(m+1);
    c[0] = A[0];
    for (int i=1; i<=m; ++i) {
        if (go[i].size() == 1) {
            c[i] = go[i][0];
        } else if (go[i].size() >= 2) {
            c[i] = build_single_circuit(go[i]);
        }
    }
    
    // for (int i: c) cout << i << ' ';
    // cout << endl;
    // for (int i: x) cout << i << ' ';
    // cout << endl;
    // for (int i: y) cout << i << ' ';
    // cout << endl;
    answer(c, x, y);
}

Compilation message (stderr)

doll.cpp: In function 'void create_circuit(int, std::vector<int>)':
doll.cpp:54:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |     for (int i=0; i+1<A.size(); ++i) go[A[i]].push_back(A[i+1]);
      |                   ~~~^~~~~~~~~

• Subtask 1: 2 / 2
• Subtask 2: 0 / 4
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 18
• Subtask 6: 0 / 56