判断字符是否回文

最新推荐文章于 2023-03-12 16:04:10 发布
转载最新推荐文章于 2023-03-12 16:04:10 发布 · 266 阅读
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<code class="hljs java has-numbering" style="background: none; padding: 0px; border-radius: 0px; color: inherit; font-family: 'Source Code Pro', monospace;font-size:undefined; display: block; white-space: pre; word-wrap: normal; box-sizing: border-box;"><span class="hljs-javadoc" style="color: rgb(136, 0, 0); box-sizing: border-box;">/*********************************************************
-  Copyright (C): 2016
-  File name    : level.c
-  Author       : - Zhaoxinan -
-  Date         : 2016年08月28日 星期日 11时14分51秒
-  Description  : 

*  *******************************************************/</span>
#include <stdio.h>
#include <string.h>

<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> islevel(<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">const</span> <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">char</span> *ptr)
{
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> i;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> found = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span>;    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//1表示是回文，0表示不是</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (ptr == NULL)  <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//有效性检测</span>
    {
        <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> -<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span>;
    }
    <span class="hljs-comment" style="color: rgb(136, 0, 0); box-sizing: border-box;">//获取字符串长度</span>
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> len = strlen(ptr);  

    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">for</span> (i = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>; i < len/<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">2</span>; i++)
    {
        <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (ptr[i] != ptr[len - i - <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span>])
        {
            found = <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>;
            <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">break</span>;
        }
    }
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> found;
}


<span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> main()
{
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">char</span> str[] = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"level"</span>;
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">char</span> src[] = <span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"hello"</span>;

    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> renum1 = islevel(str);
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">int</span> renum2 = islevel(src);

    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span> == renum1)
    {
        printf(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"is reverse str\n"</span>);
    }
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span>
    {
        printf(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"not reverse str\n"</span>);
    }

    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">if</span> (<span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">1</span> == renum2)
    {
        printf(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"is reverse str\n"</span>);
    }
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">else</span>
    {
        printf(<span class="hljs-string" style="color: rgb(0, 136, 0); box-sizing: border-box;">"not reverse str\n"</span>);
    }
    <span class="hljs-keyword" style="color: rgb(0, 0, 136); box-sizing: border-box;">return</span> <span class="hljs-number" style="color: rgb(0, 102, 102); box-sizing: border-box;">0</span>;
}
</code><ul class="pre-numbering" style="list-style: none; margin: 0px; padding: 6px 0px 40px; left: 0px; top: 0px; width: 50px; text-align: right; border-right-color: rgb(221, 221, 221); border-right-width: 1px; border-right-style: solid; position: absolute; box-sizing: border-box; background-color: rgb(238, 238, 238);"><li style="padding: 0px 5px; box-sizing: border-box;">1</li><li style="padding: 0px 5px; box-sizing: border-box;">2</li><li style="padding: 0px 5px; box-sizing: border-box;">3</li><li style="padding: 0px 5px; box-sizing: border-box;">4</li><li style="padding: 0px 5px; box-sizing: border-box;">5</li><li style="padding: 0px 5px; box-sizing: border-box;">6</li><li style="padding: 0px 5px; box-sizing: border-box;">7</li><li style="padding: 0px 5px; box-sizing: border-box;">8</li><li style="padding: 0px 5px; box-sizing: border-box;">9</li><li style="padding: 0px 5px; box-sizing: border-box;">10</li><li style="padding: 0px 5px; box-sizing: border-box;">11</li><li style="padding: 0px 5px; box-sizing: border-box;">12</li><li style="padding: 0px 5px; box-sizing: border-box;">13</li><li style="padding: 0px 5px; box-sizing: border-box;">14</li><li style="padding: 0px 5px; box-sizing: border-box;">15</li><li style="padding: 0px 5px; box-sizing: border-box;">16</li><li style="padding: 0px 5px; box-sizing: border-box;">17</li><li style="padding: 0px 5px; box-sizing: border-box;">18</li><li style="padding: 0px 5px; box-sizing: border-box;">19</li><li style="padding: 0px 5px; box-sizing: border-box;">20</li><li style="padding: 0px 5px; box-sizing: border-box;">21</li><li style="padding: 0px 5px; box-sizing: border-box;">22</li><li style="padding: 0px 5px; box-sizing: border-box;">23</li><li style="padding: 0px 5px; box-sizing: border-box;">24</li><li style="padding: 0px 5px; box-sizing: border-box;">25</li><li style="padding: 0px 5px; box-sizing: border-box;">26</li><li style="padding: 0px 5px; box-sizing: border-box;">27</li><li style="padding: 0px 5px; box-sizing: border-box;">28</li><li style="padding: 0px 5px; box-sizing: border-box;">29</li><li style="padding: 0px 5px; box-sizing: border-box;">30</li><li style="padding: 0px 5px; box-sizing: border-box;">31</li><li style="padding: 0px 5px; box-sizing: border-box;">32</li><li style="padding: 0px 5px; box-sizing: border-box;">33</li><li style="padding: 0px 5px; box-sizing: border-box;">34</li><li style="padding: 0px 5px; box-sizing: border-box;">35</li><li style="padding: 0px 5px; box-sizing: border-box;">36</li><li style="padding: 0px 5px; box-sizing: border-box;">37</li><li style="padding: 0px 5px; box-sizing: border-box;">38</li><li style="padding: 0px 5px; box-sizing: border-box;">39</li><li style="padding: 0px 5px; box-sizing: border-box;">40</li><li style="padding: 0px 5px; box-sizing: border-box;">41</li><li style="padding: 0px 5px; box-sizing: border-box;">42</li><li style="padding: 0px 5px; box-sizing: border-box;">43</li><li style="padding: 0px 5px; box-sizing: border-box;">44</li><li style="padding: 0px 5px; box-sizing: border-box;">45</li><li style="padding: 0px 5px; box-sizing: border-box;">46</li><li style="padding: 0px 5px; box-sizing: border-box;">47</li><li style="padding: 0px 5px; box-sizing: border-box;">48</li><li style="padding: 0px 5px; box-sizing: border-box;">49</li><li style="padding: 0px 5px; box-sizing: border-box;">50</li><li style="padding: 0px 5px; box-sizing: border-box;">51</li><li style="padding: 0px 5px; box-sizing: border-box;">52</li><li style="padding: 0px 5px; box-sizing: border-box;">53</li><li style="padding: 0px 5px; box-sizing: border-box;">54</li><li style="padding: 0px 5px; box-sizing: border-box;">55</li><li style="padding: 0px 5px; box-sizing: border-box;">56</li><li style="padding: 0px 5px; box-sizing: border-box;">57</li><li style="padding: 0px 5px; box-sizing: border-box;">58</li><li style="padding: 0px 5px; box-sizing: border-box;">59</li><li style="padding: 0px 5px; box-sizing: border-box;">60</li><li style="padding: 0px 5px; box-sizing: border-box;">61</li><li style="padding: 0px 5px; box-sizing: border-box;">62</li></ul><div class="save_code tracking-ad" style="top: 5px; height: 60px; right: 30px; color: rgb(255, 255, 255); font-size: 14px; display: block; position: absolute; z-index: 2; cursor: pointer; box-sizing: border-box;" data-mod="popu_249"><a target=_blank style="color: rgb(106, 57, 6); text-decoration: none; box-sizing: border-box;" href="javascript:;"><img style="border: currentColor; max-width: 100%; box-sizing: border-box;" src="http://static.blog.youkuaiyun.com/images/save_snippets.png" alt="" /></a></div><ul class="pre-numbering" style="list-style: none; margin: 0px; padding: 6px 0px 40px; left: 0px; top: 0px; width: 50px; text-align: right; border-right-color: rgb(221, 221, 221); border-right-width: 1px; border-right-style: solid; position: absolute; box-sizing: border-box; background-color: rgb(238, 238, 238);"><p> </p></ul>