2023 카카오 블라인드 채용 1차 코딩테스트 후기

지금 글을 쓰려고 보니, 붙어도 갈 생각이 없어서 후기를 작성을 안 해뒀다... 풀이 코드만 첨부한다.

7번은 시간 부족해서 문제 쳐다보지도 못 했던 기억만 남는다.

최종적으로 1차 코딩테스트는 합격했지만, 2차 코딩테스트가 ICPC와 예선과 일정이 겹쳐서 참여하지 않았다. ICPC 예선이랑 채용 일자가 겹치는 공고가 많아서 좀.. 그렇다.

 

1번

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

template<typename a, typename b>
ostream& operator<<(ostream& os, const pair<a, b>& pai) {
    os << pai.first << ' ' << pai.second;
    return os;
}
template<typename a, typename b>
istream& operator>>(istream& is, pair<a, b>& pai) {
    is >> pai.first >> pai.second;
    return is;
}

#ifdef ONLINE_JUDGE
#define endl '\n'
#endif

#define all(x) (x).begin(), (x).end()
#define INF (INT_MAX / 2)
#define MAX_N 10'005
#define MOD 1'000'000'007

int n;

int calcDate(const string& s) {
    int year = atoi(s.substr(0, 4).c_str());
    int month = atoi(s.substr(5, 2).c_str());
    int day = atoi(s.substr(8, 2).c_str());
    return day + month * 28 + year * 28 * 12;
}

vector<int> solution(string today, vector<string> terms, vector<string> privacies) {
    vector<int> answer;
    n = privacies.size();
    int todayInt = calcDate(today);
    for (int i = 0; i < n; ++i) {
        int idx = privacies[i].find(' ');
        int date = calcDate(privacies[i].substr(0, idx));
        string term = privacies[i].substr(idx + 1, privacies[i].size() - idx);
        for (int j = 0; j < terms.size(); ++j) {
            int id = terms[j].find(' ');
            string t = terms[j].substr(0, id);

            if (term.compare(t) == 0) {
                date += atoi(terms[j].substr(id + 1, terms[j].size() - id).c_str()) * 28;
                break;
            }
        }
        if (todayInt >= date) answer.emplace_back(i + 1);
    }
    return answer;
}

#ifndef ONLINE_JUDGE
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);


    return 0;
}
#endif

 

2번

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

template<typename a, typename b>
ostream& operator<<(ostream& os, const pair<a, b>& pai) {
    os << pai.first << ' ' << pai.second;
    return os;
}
template<typename a, typename b>
istream& operator>>(istream& is, pair<a, b>& pai) {
    is >> pai.first >> pai.second;
    return is;
}

#ifdef ONLINE_JUDGE
#define endl '\n'
#endif

#define all(x) (x).begin(), (x).end()
#define INF (INT_MAX / 2)
#define MAX_N 10'005
#define MOD 1'000'000'007

void adjust(int& idx, vector<int>& vec) {
    while(idx >= 0 && !vec[idx]) --idx;
}

void calc(int& idx, vector<int>& vec, int cap) {
    while(idx >= 0 && cap > 0) {
        if (!vec[idx]) --idx;
        else {
            vec[idx]--;
            cap--;
        }
    }
}

long long solution(int cap, int n, vector<int> deliveries, vector<int> pickups) {
    long long answer = 0;
    int idx1 = n - 1;
    int idx2 = n - 1;

    while(idx1 >= 0 && idx2 >= 0) {
        adjust(idx1, deliveries);
        adjust(idx2, pickups);
        answer += max(idx1, idx2) * 2 + 2;

        calc(idx1, deliveries, cap);
        calc(idx2, pickups, cap);
    }
    while(idx1 >= 0) {
        adjust(idx1, deliveries);
        answer += idx1 * 2 + 2;

        calc(idx1, deliveries, cap);
    }
    while(idx2 >= 0) {
        adjust(idx2, pickups);
        answer += idx2 * 2 + 2;

        calc(idx2, pickups, cap);
    }
    
    return answer;
}

#ifndef ONLINE_JUDGE
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);


    return 0;
}
#endif

 

3번

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

template<typename a, typename b>
ostream& operator<<(ostream& os, const pair<a, b>& pai) {
    os << pai.first << ' ' << pai.second;
    return os;
}
template<typename a, typename b>
istream& operator>>(istream& is, pair<a, b>& pai) {
    is >> pai.first >> pai.second;
    return is;
}

#ifdef ONLINE_JUDGE
#define endl '\n'
#endif

#define all(x) (x).begin(), (x).end()
#define INF (INT_MAX / 2)
#define MAX_N 10'005
#define MOD 1'000'000'007

int sale[4] = {9, 8, 7, 6};
pii ans;

void pick(const vector<vector<int>>& users, const vector<int>& emoticons, vector<pii>& prices, int toPick) {
    if (emoticons.size() == toPick) {
        pii temp = {0, 0};
        for (int i = 0; i < users.size(); ++i) {
            int totalPrice = 0;
            for (int j = 0; j < prices.size(); ++j) {
                if (users[i][0] <= prices[j].first) {
                    totalPrice += prices[j].second;
                }
            }
            if (totalPrice >= users[i][1]) {
                temp.first++;
            } else {
                temp.second += totalPrice;
            }
        }
        ans = max(ans, temp);

        return;
    }
    for (int i = 0; i < 4; ++i) {
        prices[toPick].first = (i + 1) * 10;
        prices[toPick].second = emoticons[toPick] * sale[i] / 10;
        pick(users, emoticons, prices, toPick + 1);    
    }
}

vector<int> solution(vector<vector<int>> users, vector<int> emoticons) {
    vector<int> answer;
    vector<pii> prices(emoticons.size(), {0, 0});
    pick(users, emoticons, prices, 0);

    answer.push_back(ans.first);
    answer.push_back(ans.second);
    return answer;
}

#ifndef ONLINE_JUDGE
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);


    return 0;
}
#endif

 

4번

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

template<typename a, typename b>
ostream& operator<<(ostream& os, const pair<a, b>& pai) {
    os << pai.first << ' ' << pai.second;
    return os;
}
template<typename a, typename b>
istream& operator>>(istream& is, pair<a, b>& pai) {
    is >> pai.first >> pai.second;
    return is;
}

#ifdef ONLINE_JUDGE
#define endl '\n'
#endif

#define all(x) (x).begin(), (x).end()
#define INF (INT_MAX / 2)
#define MAX_N 10'005
#define MOD 1'000'000'007

bool ans;
vector<ll> binVal;

deque<int> calcBin(ll v) {
    deque<int> ret;
    while(v) {
        ret.emplace_front(v % 2);
        v /= 2;
    }
    return ret;
}

bool check(deque<int>& arr, int l, int r) {
    int mid = (l + r) / 2;
    assert(l <= r);
    if (l == r) {
        return arr[mid];
    }
    
    bool lexpect = check(arr, l, mid - 1);
    bool rexpect = check(arr, mid + 1, r);
    if ((lexpect || rexpect) && !arr[mid]) {
        ans = false;
    }
    return arr[mid];
}

vector<int> solution(vector<long long> numbers) {
    vector<int> answer;

    binVal.emplace_back(0);
    for (int i = 1; i <= 60; ++i) {
        binVal.emplace_back((binVal.back() + 1) * 2 - 1);
    }

    for (ll number : numbers) {
        ans = true;
        deque<int> arr = calcBin(number);
        int h = lower_bound(all(binVal), arr.size()) - binVal.begin();
        for (int i = 0; i < arr.size() - binVal[h]; ++i)
            arr.emplace_front(0);

        // bool heightCheck = false;
        // for (int i = 0; i < arr.size(); i += 2) {
        //     if (arr[i] == 1) heightCheck = true;
        // }
        // if (!heightCheck) {
        //     ans = false;
        // }

        check(arr, 0, arr.size() - 1);

        answer.emplace_back(ans);
    }

    return answer;
}

#ifndef ONLINE_JUDGE
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);

    vector<ll> in;
    for (int i = 1; i <= 100000; ++i)
        in.emplace_back(i);
    auto v = solution(in);
    for (int i = 1; i <= v.size(); ++i) 
        cout << i << ": " << v[i - 1] << endl;
    return 0;
}
#endif

 

5번

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

template<typename a, typename b>
ostream& operator<<(ostream& os, const pair<a, b>& pai) {
    os << pai.first << ' ' << pai.second;
    return os;
}
template<typename a, typename b>
istream& operator>>(istream& is, pair<a, b>& pai) {
    is >> pai.first >> pai.second;
    return is;
}

#ifdef ONLINE_JUDGE
#define endl '\n'
#endif

#define all(x) (x).begin(), (x).end()
#define INF (INT_MAX / 2)
#define MAX_N 55
#define MOD 1'000'000'007

string arr[MAX_N][MAX_N];
int parent[MAX_N * MAX_N];
int find(int u){
    if (u == parent[u]) return u;
    return parent[u] = find(parent[u]);
}
void merge(int u, int v) {
    u = find(u);
    v = find(v);
    if (arr[u / MAX_N][u % MAX_N].size() && arr[v / MAX_N][v % MAX_N].size()) {
        parent[v] = u;
    } else if (arr[u / MAX_N][u % MAX_N].size()) {
        parent[v] = u;
    } else {
        parent[u] = v;
    }
}

vector<string> solution(vector<string> commands) {
    for (int i = 0; i < MAX_N * MAX_N; ++i)
        parent[i] = i;
    vector<string> answer;

    for (auto& str : commands) {
        string query = str.substr(0, str.find(' '));
        str.erase(0, str.find(' ') + 1);
        if (!query.compare("UPDATE")) {
            string s1 = str.substr(0, str.find(' '));
            str.erase(0, str.find(' ') + 1);
            bool check = str.find(' ') == string::npos;
            string s2 = str.substr(0, str.find(' '));
            str.erase(0, str.find(' ') + 1);

            if (check) {
                for (int i = 0; i < MAX_N; ++i) {
                    for (int j = 0; j < MAX_N; ++j) {
                        int v = find(i * MAX_N + j);
                        if (!arr[v / MAX_N][v % MAX_N].compare(s1)) {
                            arr[v / MAX_N][v % MAX_N] = s2;
                        }
                    }
                }
            } else {
                string s3 = str;
                int r = atoi(s1.c_str());
                int c = atoi(s2.c_str());
                int v = find(r * MAX_N + c);
                arr[v / MAX_N][v % MAX_N] = s3;
            }

        } else if (!query.compare("MERGE")) {
            int r1 = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);
            int c1 = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);
            int r2 = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);
            int c2 = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);

            int v1 = r1 * MAX_N + c1;
            int v2 = r2 * MAX_N + c2;
            merge(v1, v2);
        } else if (!query.compare("UNMERGE")) {
            int r = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);
            int c = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);

            int num = find(r * MAX_N + c);
            string temp = arr[num / MAX_N][num % MAX_N];
            for (int i = 0; i < MAX_N; ++i) {
                for (int j = 0; j < MAX_N; ++j) {
                    find(i * MAX_N + j);
                }
            }

            for (int i = 0; i < MAX_N; ++i) {
                for (int j = 0; j < MAX_N; ++j) {
                    int v = i * MAX_N + j;
                    if (find(v) == num) {
                        arr[i][j].clear();
                        parent[v] = v;
                    }
                }
            }
            arr[r][c] = temp;
        } else if (!query.compare("PRINT")) {
            int r = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);
            int c = atoi(str.substr(0, str.find(' ')).c_str());
            str.erase(0, str.find(' ') + 1);
            int v = find(r * MAX_N + c);

            if (arr[v / MAX_N][v % MAX_N].empty()) answer.emplace_back("EMPTY");
            else answer.emplace_back(arr[v / MAX_N][v % MAX_N]);
        }

        // for (int i = 1; i <= 4; ++i,cout<<endl)
        //     for (int j = 1; j <= 4; ++j)
        //         cout << arr[find(i * MAX_N + j) / MAX_N][find(i * MAX_N + j) % MAX_N] << ' ';
        // cout << endl;
    }

    return answer;
}

#ifndef ONLINE_JUDGE
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);

    return 0;
}
#endif

 

6번

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

template<typename a, typename b>
ostream& operator<<(ostream& os, const pair<a, b>& pai) {
    os << pai.first << ' ' << pai.second;
    return os;
}
template<typename a, typename b>
istream& operator>>(istream& is, pair<a, b>& pai) {
    is >> pai.first >> pai.second;
    return is;
}

#ifdef ONLINE_JUDGE
#define endl '\n'
#endif

#define all(x) (x).begin(), (x).end()
#define INF (INT_MAX / 2)
#define MAX_N 10'005
#define MOD 1'000'000'007

int calcDist(int x, int y, int r, int c) {
    return abs(x - r) + abs(y - c);
}

string gotoExit(int& x, int& y, int r, int c) {
    string ret;
    while(x < r) {
        ret.push_back('d');
        ++x;
    }
    while(y > c) {
        ret.push_back('l');
        --y;
    }
    while(y < c) {
        ret.push_back('r');
        ++y;
    }
    while(x > r) {
        ret.push_back('u');
        --x;
    }
    return ret;
}

string solution(int n, int m, int x, int y, int r, int c, int k) {
    string answer = "";

    while(k) {
        if (calcDist(x, y, r, c) == k) {
            answer.append(gotoExit(x, y, r, c));
            break;
        }
        if (calcDist(x, y, r, c) > k) {
            answer = "impossible";
            break;
        }
        if (x < n) {
            answer.push_back('d');
            ++x;
        } else if (y > 1) {
            answer.push_back('l');
            --y;
        } else if (y < m) {
            answer.push_back('r');
            ++y;
        } else {
            answer.push_back('u');
            --x;
        }
        --k;
    }

    return answer;
}

#ifndef ONLINE_JUDGE
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);

    
    return 0;
}
#endif