Submission #117496

#	Time	Username	Problem	Language	Result	Execution time	Memory
117496		zubec	Boxes with souvenirs (IOI15_boxes)	C++14	50 / 100	49 ms	12024 KiB

boxes

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

long long dp[1000100];

long long delivery(int N, int K, int L, int p[]) {

    int mid = L/2;
    int lstPos = -1;
    for (int i = 1; i <= N; i++){
        dp[i] = 1e18;
        bool bb = 0;
        int pos = p[i-1];
        if (lstPos == -1 && pos >= L-mid)
            lstPos = i;
        int pos2 = p[max(0, i-K)];
        if ((pos2 <= mid && pos <= mid) || (pos2 >= mid && pos >= mid) ){
            dp[i] = min(dp[i], dp[max(0, i-K)] + max(min(pos2, L-pos2), min(pos, L-pos))*2 );
        } else {
            dp[i] = min(dp[i], dp[max(0, i-K)] + L);
            dp[i] = min(dp[i], dp[lstPos-1] + max(min(p[lstPos-1], L-p[lstPos-1]), min(pos, L-pos))*2 );
        }
        //cout << i << ' ' << dp[i] << endl;
        /*for (int j = 1; j <= K; j++){
            if (i-j < 0)
                break;
            int pos2 = p[i-j];
            if (mid != pos2 && mid != pos && (mid-pos2)/abs(mid-pos2) != (mid-pos)/abs(mid-pos) ){
                bb = 1;
            }
            if (bb){
                dp[i] = min(dp[i], dp[i-j] + L);
            } else {
                dp[i] = min(dp[i], dp[i-j] + max(min(pos2, L-pos2), min(pos, L-pos))*2);
            }
        }*/
    }
    long long ans = dp[N];
    lstPos = -1;
    dp[N+1] = 0;
    for (int i = N; i >= 1; i--){
        dp[i] = 1e18;
        bool bb = 0;
        int pos = p[i-1];
        if (lstPos == -1 && pos <= mid)
            lstPos = i;
        int pos2 = p[min(N, i+K-1)-1];
        if ((pos2 <= mid && pos <= mid) || (pos2 >= mid && pos >= mid) ){
            dp[i] = min(dp[i], dp[min(N+1, i+K)] + max(min(pos2, L-pos2), min(pos, L-pos))*2 );
        } else {
            dp[i] = min(dp[i], dp[min(N+1, i+K)] + L);
            dp[i] = min(dp[i], dp[lstPos+1] + max(min(p[lstPos-1], L-p[lstPos-1]), min(pos, L-pos))*2 );
        }
        /*for (int j = 1; j <= K; j++){
            if (i-j < 0)
                break;
            int pos2 = p[i-j];
            if (mid != pos2 && mid != pos && (mid-pos2)/abs(mid-pos2) != (mid-pos)/abs(mid-pos) ){
                bb = 1;
            }
            if (bb){
                dp[i] = min(dp[i], dp[i-j] + L);
            } else {
                dp[i] = min(dp[i], dp[i-j] + max(min(pos2, L-pos2), min(pos, L-pos))*2);
            }
        }*/
    }
    ans = min(ans, dp[1]);
    return ans;

}

Compilation message (stderr)

boxes.cpp: In function 'long long int delivery(int, int, int, int*)':
boxes.cpp:13:14: warning: unused variable 'bb' [-Wunused-variable]
         bool bb = 0;
              ^~
boxes.cpp:44:14: warning: unused variable 'bb' [-Wunused-variable]
         bool bb = 0;
              ^~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30