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/**
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*"In the entirehttp://zzdxjyzd.com world there's nobody like me.
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*Since the beginning of time, there has never been another person like me.
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*Nobody has my smile.
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*Nobody has my eyes, my nose, my hair, my hands, or my voice."
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* 要求:用户输入一个单词,求出在这段话中出现的次数?
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* 我的思路:
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* 1.寻找一个字符串短语在一段字符串中出现几次,首先肯定是用str.indexOf("my",start)方法
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* 2.indexOf方法的返回值是int,如果找不到就会返回-1
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* 3.利用这一点,可以设定一个循环,并定义一个计数器,
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* 让计算机从段落的起始,一直找到末尾,如果找到一个就计数器+1,直到indexof返回结果为-1时,
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* 停止循环.
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* 4.注意:每一次开始找的位置,是不确定的.每一次的新位置,都是上一次找到"短语的位置"+"短语的长度"
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*/
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public class IndexDemo {
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public static void main(String[] args) {
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Scanner scan = new Scanner(System.in);
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String str = "In the entire world there's nobody like me. "
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+ "\nSince the beginning of time, "
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+ "there has never been another person like me."
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+ "\nNobody has my smile. \nNobody has my eyes, "
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+ "my nose, my hair, my hands, or my voice.";
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int count = 0;
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System.out.println("请输入需要查找的单词:");
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String key = scan.next();
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count = serachWord(str,key);
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System.out.println("短语my在段落中出现"+count+"次");
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}
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/**
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* 查找某个单词在段落中出现次数的方法
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* @param str
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* @return
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*/
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/**
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* @param str
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* @param key
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* @return
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*/
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public static int serachWord(String str,String key) {
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//记录查找次数
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int count = 0;
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//记录每次查找的下标位置,初始化
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int index = 0;
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//定义循环,如果index的位置不是-1,就一值查找
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while((index = str.indexOf(key,index))!=-1){
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//每循环一次就要明确下一次查找的位置
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index = index+key.length();
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//每查找一次计数器自增
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count ++;
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}
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return count;
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}
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}
