Question

我用C ++编写了一个代码，用于查找数组中的最大和第二大元素。代码工作正常但问题是第二大数字的位置未更新。虽然第二大数字的值是正确的，但其位置不正确。

    #include<iostream>
using namespace std;
void main()
{
    int DATA[10];
    int largestNumber, secondLargestNumber, loc1, loc2;
    cout << "Enter 10 numbers of array DATA" << endl;
    for (int i = 0; i < 10; i++)
    {
        cin >> DATA[i];
    }
    largestNumber = DATA[1];
    secondLargestNumber = DATA[2];
    loc1 = 1;
    loc2 = 2;
    if (largestNumber < secondLargestNumber)
    {
        largestNumber = DATA[2];
        secondLargestNumber = DATA[1];
    }
    for (int i = 2; i < 10; i++)
    {
        if (DATA[i]>largestNumber)
        {
            secondLargestNumber = largestNumber;
            largestNumber = DATA[i];
            loc1 = i;

        }
        else if (DATA[i]>secondLargestNumber)
        {
            secondLargestNumber = DATA[i];
            loc2 = i;
        }
    }
    cout << "Largest Number with location   :"<<largestNumber<<"    "<<loc1 << endl;
    cout << "Second Largest Number location     :" << secondLargestNumber<<"    "<<loc2 << endl;
    cin.get();
    cin.get();
}

Answer 1

我可以建议一个更简单的解决方案吗？

#include <functional>
#include <set>
#include <iostream>

int main() {
  std::set<int, std::greater<int>> s;
  int input;
  while(true) { // choose your stopping condition
    cin >> input;
    s.insert(input);
  }
  std::cout << (*s.begin()) << (*std::next(s.begin())) << std::endl;
}

Answer 2

如果你只保留位置而不是值，那么你的代码可以大大简化：

 int largest = 0, second = -1;

 for (int i = 1; i < 10; i++) {
    if( second == -1 || DATA[i] > DATA[second] ) {
        second = i;
        if( DATA[second] > DATA[largest] )
            std::swap( largest, second );
    }
 }

Answer 3

使用＆＃34; loc2 = loc1＆＃34;首先，如果块我认为它将起作用，请检查此代码，

for (int i = 2; i < 10; i++)
{
    if (DATA[i]>largestNumber)
    {
        secondLargestNumber = largestNumber;
        loc2=loc1;
        largestNumber = DATA[i];
        loc1 = i;

    }
    else if (DATA[i]>secondLargestNumber)
    {
        secondLargestNumber = DATA[i];
        loc2 = i;
    }
}

数组C ++中最大和第二大的数字

3 个答案: