二分查找

#include <iostream>

void print_arrs(const int *, int N);

void sort_arrs(int *pInt, int N);

constexpr int COUNT = 10;

int search_data(const int *pInt, int N, int k);

int main() {
    int arr[] = {1, 3, 5, 7, 6, 2, 4, 9, 8, 0};
    std::cout << "排序前:" << std::endl;
    print_arrs(arr, COUNT);
    sort_arrs(arr, COUNT);
    std::cout << "排序后:" << std::endl;
    print_arrs(arr, COUNT);
    int index = search_data(arr, COUNT, 9);
    std::cout << "the index is : " << index << std::endl;
    std::cin.get();
    return 0;
}

/**
 * 二分查找
 * @param pInt
 * @param N
 * @param k
 * @return
 */
int search_data(const int *const pInt, int N, int k) {

    for (int start = 0, end = N, mid = N / 2; start <= end; mid = (start + end) / 2) {
        if (pInt[mid] < k) {
            start = ++mid;
        } else if (pInt[mid] > k) {
            end = --mid;
        } else {
            return mid;
        }
    }
    return -1;
}


/**
 * 插入排序
 * @param pInt
 * @param N
 */
void sort_arrs(int *const pInt, int N) {
    for (int i = 1; i < N; ++i) {
        int temp = pInt[i];
        for (int j = i - 1; j >= 0 && pInt[j] > temp; --j) {
            pInt[j + 1] = pInt[j];//移出空位
            pInt[j] = temp;//新排落位
        }
    }
}

void print_arrs(const int *pInt, int N) {
    for (int i = 0; i < N; ++i) {
        std::cout << pInt[i] << "\t";
    }
    std::cout << std::endl;
}