编程算法 - 翻转单词顺序 代码(C)

翻转单词顺序 代码(C)

本文地址: http://blog.csdn.net/caroline_wendy

题目: 输入一个英文句子, 翻转句子中单词的顺序, 但单词内字符的顺序不变.

首先翻转(reverse)整个句子, 然后查找空格, 如遇到空格, 则翻转前面的单词, 或遇到结束符, 相同进行翻转.

代码:

/*
 * main.cpp
 *
 *  Created on: 2014.9.19
 *      Author: spike
 */

#include <iostream>
#include <vector>
#include <climits>

#include <cstring>

using namespace std;

void Reverse(char* begin, char* end) {
	if (begin == NULL || end == NULL)
		return;
	while(begin < end) {
		char tmp = *begin;
		*begin++ = *end;
		*end-- = tmp;
	}
}

char* ReverseWords(char* data) {
	if (data == NULL) return NULL;
	int len = strlen(data);
	char* begin = data;
	char* end = &data[len-1];
	Reverse(begin, end);
	begin = end = data;
	while(*begin != '\0') {
		if (*begin == ' ') {
			begin++;
			end++;
		} else if (*end == ' ' || *end == '\0') {
			Reverse(begin, --end);
			begin = ++end;
		} else {
			++end;
		}
	}
	return data;
}

int main(void)
{
	char data[] = "I am Spike.";
	char* res = ReverseWords(data);
	cout << res << endl;

    return 0;
}

输出:

Spike. am I