一个小问题有点不懂 - 黑马程序员技术交流社区

public class StringTest {
public static void main(String[] args) {
String bigString = "nbasdnbafllgnbahjnbakqqqqlnba";
String smallString = "nba";
int count = searchCount(bigString, smallString);
System.out.println(count);
}
public static int searchCount(String bigString, String smallString) {
int count = 0;
int index = bigString.indexOf(smallString);
while (index != -1) {
count++;
bigString = bigString.substring(index + smallString.length());//这为什么还用index+ smallString.length()
index = bigString.indexOf(smallString);
}
return count;
}

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public class StringTest {
public static void main(String[] args) {
String bigString = "nbasdnbafllgnbahjnbakqqqqlnba";
String smallString = "nba";
int count = searchCount(bigString, smallString);
System.out.println(count);
}
public static int searchCount(String bigString, String smallString) {
int count = 0; // 定义统计变量count,并致零，用于存放字符串"nba"在"nbasdnbafllgnbahjnbakqqqqlnba"粗线的次数
int index = bigString.indexOf(smallString); // 调用indexof方法查找，定义小字符串第一次出现在大字符串中的索引值
while (index != -1) { //当index不为-1，说明小字符串在大字符窜中，进入while循环开始查找，为-1说明不在大字符窜中，直接返回count
count++; //count记录小字符串出现的吃树
bigString = bigString.substring(index + smallString.length()); // 每次查找到，就从新生成一次大字符窜，新字符串就是原字符串截去小字符串（包括小字符串前面的）剩下的
index = bigString.indexOf(smallString); // 由于大字符窜变化了，将小字符串出现在新字符串的索引值从新赋给index
}
return count;
}

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