Cracking the coding interview--Q1.2

题目

原文：

Write code to reverse a C-Style String. (C-String means that “abcd” is represented as five characters, including the null character.)

译文：

写代码翻转一个C风格的字符串。(C风格的意思是"abcd"需要用5个字符来表示，包含末尾的 结束字符)

解答

这道题如果就是要考察你有没有注意到C风格字符串最后的那个结束符，那我觉得还是像书 上写的那样，在代码中有所体现。代码如下：

java：

package cha1;

public class A002 {
    
    public static char[] swap(char[] cstr) {
        int len = cstr.length;
        char[] cs = new char[len];
        for (int i=0; i<len; i++) {
            cs[len-i-1] = cstr[i];
        }
        return cs;
    }
    
    public static void main(String[] args) {
        char[] cs = new char[5];
        cs[0] = 'l';
        cs[1] = 'o';
        cs[4] = 'u';
        System.out.println(swap(cs));
    }
}

c++

#include <iostream>
#include <cstring>
using namespace std;

void swap(char &a, char &b){
    a = a^b;
    b = a^b;
    a = a^b;
}

void reverse2(char *s){
    int n = strlen(s);
    for(int i=0; i<n/2; ++i)
        swap(s[i], s[n-i-1]);
}

void reverse1(char *s){
    if(!s) return;
    char *p = s, *q = s;
    while(*q) ++q;
    --q;
    while(p < q)
        swap(*p++, *q--);
}

int main(){
    char s[] = "1234567890";
    reverse1(s);
    cout<<s<<endl;
    return 0;
}