如何找到最大乘积的总和？

问：

当给定 n 个整数时，您可以将两个数字相乘或保持原样。我编写了一个算法来找到所有值加在一起的最大值。

例如，输入为：

9（数组长度） -1 -8 2 1 3 6 -5 0 1

输出需要为 62：

62=-8x-5+0x-1+6x3+2+1+1

如果数组是 ，则答案应为 91。如果数组是 ，则答案应为 838。7 4 1 2 5 3 1 9 0-13 7 -12 13 -8 4 12 7 15 6 -2 10 9 15 4 1 -15

我是这样编写代码的：

#include <iostream>
#include "sop.h"
using namespace std;

sop::sop() {
    this->num = 0;
    this->array = NULL;
}

sop::sop(int* a, int n) {
    this->num = n;
    this->array = new int[n];
    for (int i = 0; i < n; i++) this->array[i] = a[i];
}

sop::~sop() {
    if (this->array) {
        delete[] this->array;
    }
    this->num = 0;
    this->array = NULL;
}

void sop::printArray(void) {
    if (!this->num)  return;
    for (int i = 0; i < num; i++) cout << array[i] << "  ";
    cout << endl;
}

int myMax(int a, int b) {
    return (a > b) ? a : b;
}

int sop::maxSOP() {
    if (num == 0) return 0;
    if (num == 1) return array[0];

    int maxSum = array[0]; // Initialize maxSum to the first element
    int currentMax = array[0]; // Initialize currentMax to the first element

    for (int i = 1; i < num; i++) {
        int temp = currentMax; // Store the previous currentMax

        // Calculate the current maximum product including the current element
        currentMax = myMax(array[i], myMax(currentMax * array[i], temp * array[i]));

        // Update maxSum with the maximum of maxSum and currentMax
        maxSum = myMax(maxSum, currentMax);
    }

    return maxSum;
}

maxSOP这就是我所做的。myMax

在此代码中，结果是 288，而不是 62。我不知道为什么。你能修复这个代码吗？我将向您展示可以帮助您修复此代码的其他文件。

其他文件.cpp

#include <iostream>
#include <fstream>
#include "sop.h"
using namespace std;

int main(int argc, char* argv[]) {
    int i = 0;
    int num = 0;
    int* array = NULL;
    ifstream fin;
    sop* _sop = NULL;

    if (argc > 1) {
        fin.open(argv[1]);
        if (!fin.is_open()) {
            cerr << "File " << argv[1] << " does not exist!" << endl;
            exit(0);
        }
        fin >> num;
        array = new int[num];
        for (i = 0;i < num;i++)        fin >> array[i];
        fin.close();
    }
    else {
        cin >> num;
        array = new int[num];
        for (i = 0;i < num;i++)        cin >> array[i];
    }

    _sop = new sop(array, num);
    cout << "Input array: ";
    _sop->printArray();
    cout << "Maximum sum of products = " << _sop->maxSOP() << endl;
    delete _sop;
    if (array)       delete[] array;
    array = NULL;
    return 0;
}

otherheader.h

#include <iostream>
#include <fstream>
#include "sop.h"
using namespace std;

int main(int argc, char* argv[]) {
    int i = 0;
    int num = 0;
    int* array = NULL;
    ifstream fin;
    sop* _sop = NULL;

    if (argc > 1) {
        fin.open(argv[1]);
        if (!fin.is_open()) {
            cerr << "File " << argv[1] << " does not exist!" << endl;
            exit(0);
        }
        fin >> num;
        array = new int[num];
        for (i = 0;i < num;i++)        fin >> array[i];
        fin.close();
    }
    else {
        cin >> num;
        array = new int[num];
        for (i = 0;i < num;i++)        cin >> array[i];
    }

    _sop = new sop(array, num);
    cout << "Input array: ";
    _sop->printArray();
    cout << "Maximum sum of products = " << _sop->maxSOP() << endl;
    delete _sop;
    if (array)       delete[] array;
    array = NULL;
    return 0;
}