import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
public static void main(String[] args) {
final String regex = "(\\/)(\\*)(.|\\n)*?\\2\\1|(\\/\\/.*)";
final String string = "#include<stdio.h>\n"
+ "#include<stdlib.h>\n"
+ "typedef struct Node\n"
+ "{\n"
+ " int data;\n"
+ " struct Node *next;\n"
+ " struct Node *prev;\n"
+ "}node;\n"
+ "void insert(node *pointer, int data)\n"
+ "{\n"
+ " /* Iterate through the list till we encounter the last node.*/\n"
+ " while(pointer->next!=NULL)\n"
+ " {\n"
+ " pointer = pointer -> next;\n"
+ " }\n"
+ " /* Allocate memory for the new node and put data in it.*/\n"
+ " pointer->next = (node *)malloc(sizeof(node));\n"
+ " (pointer->next)->prev = pointer;\n"
+ " pointer = pointer->next;\n"
+ " pointer->data = data;\n"
+ " pointer->next = NULL;\n"
+ "}\n"
+ "int find(node *pointer, int key)\n"
+ "{\n"
+ " pointer = pointer -> next; //First node is dummy node.\n"
+ " /* Iterate through the entire linked list and search for the key. */\n"
+ " while(pointer!=NULL)\n"
+ " {\n"
+ " if(pointer->data == key) //key is found.\n"
+ " {\n"
+ " return 1;\n"
+ " }\n"
+ " pointer = pointer -> next;//Search in the next node.\n"
+ " }\n"
+ " /*Key is not found */\n"
+ " return 0;\n"
+ "}\n"
+ "void delete(node *pointer, int data)\n"
+ "{\n"
+ " /* Go to the node for which the node next to it has to be deleted */\n"
+ " while(pointer->next!=NULL && (pointer->next)->data != data)\n"
+ " {\n"
+ " pointer = pointer -> next;\n"
+ " }\n"
+ " if(pointer->next==NULL)\n"
+ " {\n"
+ " printf(\"Element %d is not present in the list\\n\",data);\n"
+ " return;\n"
+ " }\n"
+ " /* Now pointer points to a node and the node next to it has to be removed */\n"
+ " node *temp;\n"
+ " temp = pointer -> next;\n"
+ " /*temp points to the node which has to be removed*/\n"
+ " pointer->next = temp->next;\n"
+ " temp->prev = pointer;\n"
+ " /*We removed the node which is next to the pointer (which is also temp) */\n"
+ " free(temp);\n"
+ " /* Beacuse we deleted the node, we no longer require the memory used for it .\n"
+ " free() will deallocate the memory.\n"
+ " */\n"
+ " return;\n"
+ "}\n"
+ "void print(node *pointer)\n"
+ "{\n"
+ " if(pointer==NULL)\n"
+ " {\n"
+ " return;\n"
+ " }\n"
+ " printf(\"%d \",pointer->data);\n"
+ " print(pointer->next);\n"
+ "}\n"
+ "int main()\n"
+ "{\n"
+ " /* start always points to the first node of the linked list.\n"
+ " temp is used to point to the last node of the linked list.*/\n"
+ " node *start,*temp;\n"
+ " start = (node *)malloc(sizeof(node));\n"
+ " temp = start;\n"
+ " temp -> next = NULL;\n"
+ " temp -> prev = NULL;\n"
+ " /* Here in this code, we take the first node as a dummy node.\n"
+ " The first node does not contain data, but it used because to avoid handling special cases\n"
+ " in insert and delete functions.\n"
+ " */\n"
+ " printf(\"1. Insert\\n\");\n"
+ " printf(\"2. Delete\\n\");\n"
+ " printf(\"3. Print\\n\");\n"
+ " printf(\"4. Find\\n\");\n"
+ " while(1)\n"
+ " {\n"
+ " int query;\n"
+ " scanf(\"%d\",&query);\n"
+ " if(query==1)\n"
+ " {\n"
+ " int data;\n"
+ " scanf(\"%d\",&data);\n"
+ " insert(start,data);\n"
+ " }\n"
+ " else if(query==2)\n"
+ " {\n"
+ " int data;\n"
+ " scanf(\"%d\",&data);\n"
+ " delete(start,data);\n"
+ " }\n"
+ " else if(query==3)\n"
+ " {\n"
+ " printf(\"The list is \");\n"
+ " print(start->next);\n"
+ " printf(\"\\n\");\n"
+ " }\n"
+ " else if(query==4)\n"
+ " {\n"
+ " int data;\n"
+ " scanf(\"%d\",&data);\n"
+ " int status = find(start,data);\n"
+ " if(status)\n"
+ " {\n"
+ " printf(\"Element Found\\n\");\n"
+ " }\n"
+ " else\n"
+ " {\n"
+ " printf(\"Element Not Found\\n\");\n\n"
+ " }\n"
+ " }\n"
+ " }\n\n\n"
+ "}";
final Pattern pattern = Pattern.compile(regex);
final Matcher matcher = pattern.matcher(string);
while (matcher.find()) {
System.out.println("Full match: " + matcher.group(0));
for (int i = 1; i <= matcher.groupCount(); i++) {
System.out.println("Group " + i + ": " + matcher.group(i));
}
}
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html