關於字符串的匹配問題;主字符串1 —> str1 = "xxxxI write themxxxxxxxx I write them here shows what I have been learning." ;
字符串2 —> str2= "I write them here shows what I have been learning.";
若字符串1包含字符串2,則返回開始出現的位置;否則返回-1;
參考來源：https://blog.csdn.net/MrTumnus/article/details/121679134
package utitled;
public class ExhaustiveAlgorithmDemo {
/**
* 窮舉法(暴力法)
* 若使用暴力匹配的方式,需要依次尋找是否存在;假如父級字符串str1 有個指針i ; 子級字符串str2 有個指著j;
* (1)當str1.charAt( i ) == str2.charAt( j ) ;i+=1;j+=1,兩個字符串的指針均向後移動;
* (2)若當前不相等時,則需要將子級字符串str2的指針j 歸零; 然後是字符串str1的指針需要回溯:i=i-(j-1)
*/
public static void main(String[] args) {
String s1 = "xxxxI write themxxxxxxxx I write them here shows what I have been learning.";
String s2 = "I write them here shows what I have been learning.";
int i = exhaustiveAlgorithm(s1, s2);
System.out.printf("匹配字串從index=%d開始", i);
}
private static int exhaustiveAlgorithm(String s1, String s2) {
char[] chars1 = s1.toCharArray();
char[] chars2 = s2.toCharArray();
int i = 0, j = 0;
while (i < chars1.length && j < chars2.length) {
if (chars1[i] == chars2[j]) {
i++;
j++;
} else {
i = i - (j - 1);
j = 0;
}
}
if (j == chars2.length) {
return i - chars2.length;
} else {
return -1;
}
}
}如有敘述錯誤，還請不吝嗇留言指教，thanks!