Question

我的任务是：创建一个方法来搜索一个无序的整数数组，如果找到该值，则返回其在数组中的位置索引，如果未找到，则返回-1。

如果它在索引0中，它只找到我输入的数字，否则就是说找不到它。我不知道出了什么问题，当我初始化我自己的数组时它正在工作，但现在它不会因为我让用户创建自己的数组而赢了。

任何帮助都会很棒！谢谢！

到目前为止，我的代码是：

#include <iostream>

using namespace std;


//SearchArray prototype
int SearchArray( int arInt[], int elementAmount, int intSearched);


int main()

{
    int arInt[50];
    int elementAmount;
    int intSearched = 0;
    int i;

    cout << "How many elements would you like to add to your array?\n";
    cin >> elementAmount;

    for( i = 0; i < elementAmount; i++)
    {
        cout << "Enter Number: ";
        cin >> arInt[i];
    }

        cout << "Search array for integer:\n";
        cin >> intSearched;

        //Call search array method
        SearchArray(arInt, elementAmount, intSearched);


    system("pause");
    return 0;
}


int SearchArray( int arInt[], int elementAmount, int intSearched)
{
        int i;
        bool foundInt = false;

        for (i=0; i < elementAmount; i++)
        {
            if( arInt[i] == intSearched)
            {
                foundInt = true;
                cout << "Integer was found in array at index " << i << endl;
            }
            else if (!foundInt)
            {
                cout << "Integer was not found in array\n";

                system("pause");
                return -1;
            }


        }

}

Answer 1

在代码中的SearchArray方法中添加了以下代码，并且工作正常

int SearchArray( int arInt[], int elementAmount, int intSearched)
{
    for(int i=0; i< elementAmount; i++)
    {
        if (arInt[i] == intSearched)
            return i;
    }
    // element not found!
    return -1;
}

在main的末尾添加以下内容以检索ans

int ans = SearchArray(arInt, elementAmount, intSearched);
cout<<"Indexed of the element"<<ans<<endl;

Answer 2

那是因为你总是在第一个元素上结束你的搜索。假设数组是

arr=[3,5,7] and intSearched is 5.

现在您的SearchArray()函数foundInt最初设置为false。因此，当i = 0 and arInt[i] == intSearched条件不成立时，它会转到else语句，因为foundInt是false。然后从那里返回-1。像下面这样的东西会更简单并完成工作：

int SearchArray(int *arInt, int elementAmount, int intSearched)
{
    int i;
    for(i=0; i < elementAmount; i++)
    {
        if(arInt[i] == intSearched)
        {
            cout << "Integer was found in array at index " << i << endl;
            return 1;
        }
    }
    cout << "Integer was not found in array\n";
    system("pause");
    return 0;
}

无序数组线性搜索c ++

2 个答案: