比较两个字符串,找出最大的相同子串

public class Test05 {
public static void main(String[] args) {
String str1="adfdfghellojavabggiijbffbfhelloworldsdrtyiooipwtfdv";
//String str1="ncvkhvkdfhfhieuwiqwewhellojavaecvbvbnbnqe";
String str2="ncvkhvkdfhfhieuwiqwewhellojavaecvbvbnbndhelloworldfadfafdgagdqe";
System.out.println(test05(str1,str2));
}

public static String test05(String str1,String str2){
int len=str2.length();
for (int i = 0; i < str2.length(); i++) {//外层循环,最大的循环次数
for (int j = 0,k=len-i;k<=len ; j++,k++) {//内层循环,截取子串并进行比较
String str3=str2.substring(j, k);//分别从两端截取,得到子串
//截取子串的长度为k-j,即为len-i-j,随着i的增加,子串长度不断变小
//假如字符串为abcd,第一次截取子串阿为abcd,第二次bcd,第三次abc,第四次bc....依此类推
if (str1.contains(str3)) {
return str3; //进行比较,返回值
}
}
}

return null;
}
}

同样的方法，稍有不同，返回一个数组的所有连续的子串

public class Demo0518 {
public static void main(String[] args) {
int[] arr = new int[] { 1, 2, -5, 56, 3, 7, 9, 10, -42, 45 };
Demo(arr, 0, arr.length-1);
}

public static void Demo(int[] arr, int start, int end) {
/**
* 0<=start<=end<=arr.length-1
*/
for (int i = start; i <= end; i++) {
for (int x=i,y=end; x <=y; y--) {
ArrPrint(arr, x, y);
System.out.println("子串的和： "+Sum(arr, x, y));
System.out.println();
}
}
}

public static void ArrPrint(int[] arr,int start ,int end) {
System.out.print("子串：");
for (int i = start; i <= end; i++) {
System.out.print(arr[i]+" ");
}
System.out.println();
}
public static int Sum(int[] arr,int start ,int end){
int sum=0;
for (int i = start; i <= end; i++) {
sum+=arr[i];
}
return sum;
}
}