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
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
#include <iostream>
#include <numeric>
#include <vector>

#include "kanapka.h"
#include "message.h"

using namespace std;

#define OUTPUT(x) if(MyNodeId() == 0) {cout << x << endl;}

struct LeastTasty {
    long long continuous = 0;
    long long prefix = 0;
    long long suffix = 0;
    long long total = 0;
};

bool beats(long long int sum, long long int result) { return sum < result; }

bool shouldTakePrevious(long long int sum) { return sum < 0; }

LeastTasty calculateSum(long long int start, long long end) {
    LeastTasty sum;
    LeastTasty leastTasty;
    vector<long long> tastes(end-start);
    for (int j = start; j < end; ++j) {
        tastes.push_back(GetTaste(j));
    }

    leastTasty.total = accumulate(tastes.begin(), tastes.end(), 0);
    for (long long i = start; i < end; ++i) {
        if(shouldTakePrevious(sum.continuous))
            sum.continuous += GetTaste(i);
        else
            sum.continuous = GetTaste(i);
        if(beats(sum.continuous, leastTasty.continuous))
            leastTasty.continuous = sum.continuous;
    }

    for (long long i = start; i < end; ++i) {
        sum.prefix += GetTaste(i);
        if(beats(sum.prefix, leastTasty.prefix))
            leastTasty.prefix = sum.prefix;
    }

    for (long long i = end-1; i >= start; --i) {
        sum.suffix +=GetTaste(i);
        if(beats(sum.suffix, leastTasty.suffix))
            leastTasty.suffix = sum.suffix;
    }

    return leastTasty;
}

vector<LeastTasty> instanceResults(NumberOfNodes());

int main() {
    ios_base::sync_with_stdio(false);

    long long n = GetN();

    auto instanceNumber = NumberOfNodes();
    long long tastesPerNode = n / instanceNumber;
    long long reminder = n % instanceNumber;

    auto nodeId = MyNodeId();
    long long start = nodeId * tastesPerNode;
    long long end = (nodeId+1) * tastesPerNode + (nodeId<reminder ? 1:0);

    LeastTasty instanceResult = calculateSum(start, end);

    long long finalResult = 0;

    if(MyNodeId() > 0) {
        PutLL(0, instanceResult.prefix);
        PutLL(0, instanceResult.suffix);
        PutLL(0, instanceResult.continuous);
        PutLL(0, instanceResult.total);
        Send(0);
    } else { //id = 0
        instanceResults.push_back(instanceResult);
        for (int inst = 1; inst < NumberOfNodes(); ++inst) {
            Receive(inst);
            LeastTasty otherResult;
            otherResult.prefix = GetLL(inst);
            otherResult.suffix = GetLL(inst);
            otherResult.continuous = GetLL(inst);
            otherResult.total = GetLL(inst);
            instanceResults.push_back(otherResult);
        }

        long long leastTastySum = 0;
        for(auto it = instanceResults.begin(); it != instanceResults.end(); it++) {
            leastTastySum = it->continuous;
            if(beats(leastTastySum, finalResult)) {
                finalResult = leastTastySum;
            }
        }

        for(auto it = instanceResults.begin(); it != instanceResults.end(); it++) {
            leastTastySum = it->prefix;
            auto previousLeastTastySum = leastTastySum;
            for(auto it2 = it+1; it2 != instanceResults.end(); it2++) {
                leastTastySum += it2->suffix;
                if(beats(leastTastySum, finalResult))
                    finalResult = leastTastySum;
                leastTastySum = previousLeastTastySum + it2->total;
                previousLeastTastySum = leastTastySum;
            }
            if(leastTastySum != instanceResults[instanceResults.size() - 1].prefix) {
                leastTastySum = previousLeastTastySum + instanceResults[instanceResults.size() - 1].total;
                if(beats(leastTastySum, finalResult))
                    finalResult = leastTastySum;
            }
        }

        //special cases
        leastTastySum = accumulate(instanceResults.begin(), instanceResults.end(), 0, [](long long acc, LeastTasty right) -> long long{
            return acc + right.total;
        });
        if(beats(leastTastySum, finalResult))
            finalResult = leastTastySum;
        leastTastySum = instanceResults[instanceResults.size() - 1].total;
        if(beats(leastTastySum, finalResult))
            finalResult = leastTastySum;

        long long totalSum = 0;
        for(auto it = instanceResults.begin(); it != instanceResults.end(); it++) {
            totalSum += it->total;
        }
        if(finalResult >= 0) {
            OUTPUT(totalSum) //whole sandwich is tasty
        } else {
            OUTPUT(totalSum - finalResult)
        }
    }

    return 0;
}