1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
#include <iostream>
#include <math.h>
#include "kanapka.h"
#include "message.h"

#define LL long long

using namespace std;


struct partialResult {
    LL totalTaste;
    LL leftMaxTaste;
    LL rightMaxTaste;
};

partialResult partialProcessing(LL firstPiece, LL lastPiece) {
    LL totalTaste = 0, leftMaxTaste = 0, localWorstTaste = 0;
    partialResult result;

    for(LL i = firstPiece; i < lastPiece; i++) {
        totalTaste += GetTaste(i);
        if (totalTaste > leftMaxTaste)
            leftMaxTaste = totalTaste;
        if (totalTaste - leftMaxTaste < localWorstTaste)
            localWorstTaste = totalTaste - leftMaxTaste;
    }

    result.totalTaste = totalTaste;
    result.leftMaxTaste = leftMaxTaste;
    result.rightMaxTaste = totalTaste - leftMaxTaste - localWorstTaste;

    return result;
}

LL getPiecesPerNodesCount(LL piecesCount, int numberOfNodes) {
    return piecesCount / numberOfNodes + 1;
}


int main()
{
    LL piecesCount, firstPiece, lastPiece, piecesPerNodesCount;
    int numberOfNodes, nodeId;

    numberOfNodes = NumberOfNodes();
    nodeId = MyNodeId();

    piecesCount = GetN();

    piecesPerNodesCount = getPiecesPerNodesCount(piecesCount, numberOfNodes);
    firstPiece = nodeId * piecesPerNodesCount;
    if (firstPiece >= piecesCount)
        return 0;
    lastPiece = firstPiece + piecesPerNodesCount;
    if (lastPiece > piecesCount)
        lastPiece = piecesCount;

    partialResult result = partialProcessing(firstPiece, lastPiece);

    if (nodeId > 0) {
        PutLL(0, result.totalTaste);
        PutLL(0, result.leftMaxTaste);
        PutLL(0, result.rightMaxTaste);
        Send(0);
        return 0;
    } else {
        for (int i = 1; i < numberOfNodes; i++) {
            if (i*piecesPerNodesCount >= piecesCount)
                break;

            LL rTotalTaste, rleftMaxTaste, rRightMaxTaste;

            Receive(i);
            rTotalTaste = GetLL(i);
            rleftMaxTaste = GetLL(i);
            rRightMaxTaste = GetLL(i);

            if (result.leftMaxTaste < result.totalTaste + rleftMaxTaste) {
                result.leftMaxTaste = result.totalTaste + rleftMaxTaste;
                result.rightMaxTaste = rRightMaxTaste;
            } else {
                result.rightMaxTaste = max(0LL, max(rRightMaxTaste, result.rightMaxTaste + rTotalTaste));
            }
            result.totalTaste += rTotalTaste;
        }
    }

    cout << result.leftMaxTaste + result.rightMaxTaste << endl;
    return 0;
}