willcool4ever • 递归实现basename命令

#include <iostream>
#include <arpa/inet.h>
#include <string.h>
using namespace std;

void xy_log1(const char *path, bool &is_ok)
{
    if (path == nullptr)
        return;

    if (strlen(path) == 0)
        return;

    // cout << path << endl;
    path++;
    xy_log1(path, is_ok);
    path--;
    if (path[0] == '/' && is_ok == false)
    {
        cout << path+1 << endl;
        is_ok = true;
    }
}

void xy_log2(const char *path, char **is_ok_p)
{
    if (path == nullptr)
        return;

    if (strlen(path) == 0)
        return;

    // cout << path << endl;
    path++;
    xy_log2(path, is_ok_p);
    path--;
    if (path[0] == '/' && *is_ok_p == nullptr)
    {
        //cout << path << endl;
        *is_ok_p = (char *)path+1;
    }
}

const char *xy_log3(const char *path)
{
    // 0、去除非法
    if (path == nullptr)
        return path;

    // 1、设定递归基
    if (strlen(path) == 0)
        return nullptr;

    // 2、完成递的过程
    path++;
    auto ret = xy_log3(path);

    // 3、完成归的过程
    path--;

    if (path[0] == '/' && ret == nullptr)
    {
        ret = (char *)path+1;
    }

    return ret;
}

int main(int argc, char const *argv[])
{

    {
        bool is_ok = false;
        xy_log1("/etc/xxx/a.cpp", is_ok);
    }

    {
        char *is_ok_p = nullptr;
        xy_log2("/etc/xxx/a.cpp", &is_ok_p);
        cout << is_ok_p << endl;
    }

    {
        cout << xy_log3("/etc/xxx/a.cpp") << endl;
    }

    return 0;
}

➜  ~ g++ -std=c++11  test.cpp  -o test
➜  ~ ./test
a.cpp
a.cpp
a.cpp