[C++] Programmers | 택배 배달과 수거하기

택배 배달과 수거하기

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✅ Accept Code

// programmers week1-1
// 택배 배달과 수거하기

#include <bits/stdc++.h>

using namespace std;

int totalD = 0;
int totalP = 0;
int dis;

int goDelivery(int cap, int n, vector<int> &deliveries, vector<int> &pickups) {
    int len = 0;
    int cnt = cap;
    for (int i = n - 1; i >= 0; i--) {
        if (deliveries[i] == 0) continue;
        if (len == 0) len = i + 1;
        if (deliveries[i] <= cnt) {
            cnt -= deliveries[i];
            totalD--;
            deliveries[i] = 0;
        } else {
            deliveries[i] -= cnt;
            cnt = 0;
        }

        if (cnt == 0 || totalD == 0) {
            return len;
        }
    }
    return len;
}

int goPickUp(int cap, int n, vector<int> &deliveries, vector<int> &pickups) {
    int cnt = 0;
    int len = 0;
    for (int i = n - 1; i >= 0; i--) {
        if (pickups[i] == 0) continue;
        if (len == 0) len = i + 1;
        if (pickups[i] > cap - cnt) {
            pickups[i] -= (cap - cnt);
            cnt = cap;
        } else {
            cnt += pickups[i];
            pickups[i] = 0;
            totalP--;
        }
        if (cnt == cap) {
            return len;
        }
    }
    return len;
}

long long solution(int cap, int n, vector<int> deliveries, vector<int> pickups) {
    for (int i = 0; i < n; i++) {
        if (deliveries[i] != 0) totalD++;
        if (pickups[i] != 0) totalP++;
    }

    long long result = 0;
    dis = n - 1;
    while (1) {
        int d = 0, p = 0;
        if (totalD == 0 && totalP == 0) break;
        if (totalD != 0) {
            d = goDelivery(cap, dis + 1, deliveries, pickups);
        }
        if (totalP != 0) {
            p = goPickUp(cap, dis + 1, deliveries, pickups);
        }

        for (int i = dis; i >= 0; i--) {
            if (deliveries[i] == 0 && pickups[i] == 0) dis--;
            else break;
        }
        int len = 2 * max(d, p);
        result += len;
    }

    return result;
}