用C++代码：使用模板类对给定的查找集合顺序查找与给定值k相等的元素，对给定的查找集合折半查找与给定值k相等的元素

顺序查找：

#include <iostream>
using namespace std;

template <class T>
int sequentialSearch(T arr[], int n, T key) {
    for (int i = 0; i < n; i++) {
        if (arr[i] == key) {
            return i;
        }
    }
    return -1;
}

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int n = sizeof(arr) / sizeof(arr[0]);
    int key = 3;
    int index = sequentialSearch(arr, n, key);
    if (index != -1) {
        cout << "Element found at index " << index << endl;
    } else {
        cout << "Element not found" << endl;
    }
    return 0;
}

折半查找：

#include <iostream>
using namespace std;

template <class T>
int binarySearch(T arr[], int n, T key) {
    int low = 0, high = n - 1;
    while (low <= high) {
        int mid = (low + high) / 2;
        if (arr[mid] == key) {
            return mid;
        } else if (arr[mid] < key) {
            low = mid + 1;
        } else {
            high = mid - 1;
        }
    }
    return -1;
}

int main() {
    int arr[] = {1, 2, 3, 4, 5};
    int n = sizeof(arr) / sizeof(arr[0]);
    int key = 3;
    int index = binarySearch(arr, n, key);
    if (index != -1) {
        cout << "Element found at index " << index << endl;
    } else {
        cout << "Element not found" << endl;
    }
    return 0;
}