Submission #1148583

#	Time	Username	Problem	Language	Result	Execution time	Memory
1148583		weakweakweak	Binary Subsequences (info1cup17_binary)	C++20	43 / 100	57 ms	61764 KiB

binary

#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast")
using pii = pair<int,int>;
#define fs first 
#define sc second

int cnt[2010] = {0};
int dp[2010][2010]; // dp[目前dp值][上一個0] = 上一個1
pii lst[2010][2010];
int len[2010][2010] = {0};
char cc[2010][2010];
string s[2010];
queue<int> q[2010];

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);
    for (int i = 0; i <= 2005; i++) for (int j = 0; j <= 2005; j++) dp[i][j] = 888888, len[i][j] = 114514;
    dp[1][0] = 0;
    len[1][0] = 0;
    
    q[1].push(0);

    for (int i = 1; i <= 2005; i++) {
        while (q[i].size()) {
            int lst0 = q[i].front(); q[i].pop();
            int lst1 = dp[i][lst0];
            { // 接 0
                int ni = i*2 - lst0;
                if (ni <= 2005) {
                    cnt[ni]++;
                    int n0 = i, n1 = lst1;
                    q[ni].push(n0);
                    cc[ni][n0] = '0';
                    dp[ni][n0] = n1;
                    lst[ni][n0] = make_pair(i,lst0);
                    len[ni][n0] = len[i][lst0] + 1;
                }
            }
            { // 接 0
                int ni = i*2 - lst1;
                if (ni <= 2005) {
                    cnt[ni]++;
                    int n0 = lst0, n1 = i;
                    q[ni].push(n0);
                    cc[ni][n0] = '1';
                    dp[ni][n0] = n1;
                    lst[ni][n0] = make_pair(i,lst0);
                    len[ni][n0] = len[i][lst0] + 1;
                }
            }
        }
    }

    int t;
    cin >> t;
    while (t--) {
        int k;
        cin >> k;
        k++;
        cout << cnt[k] << '\n';
        int ansid = 0;
        for (int i = 0; i <= 2005; i++) if (len[k][i] < len[k][ansid]) ansid = i;

        vector<char> ans;
        pii me = {k, ansid};
        while (me != make_pair(1,0)) {
            ans.push_back(cc[me.fs][me.sc]);
            me = lst[me.fs][me.sc];
        }
        reverse(ans.begin(), ans.end());
        for (char c : ans) cout << c << ' '; cout << '\n';
    }
}

• Subtask 1: 43 / 43
• Subtask 2: 0 / 39
• Subtask 3: 0 / 18