antrix1989

#import <Foundation/Foundation.h>

//Given a linked list, swap every two adjacent nodes and return its head.
//For example,
//Given 1->2->3->4, you should return the list as 2->1->4->3.
//Your algorithm should use only constant space. You may not modify the values in the list, only nodes itself can be changed.
// 6:03 PM

@interface Node: NSObject
@property (nonatomic) Node *nextNode;

antrix1989

#import <Foundation/Foundation.h>

// Merge Two Sorted Lists.
// 1 -> 2 -> 3 -> 4
// 5 -> 6 -> 7

@interface Node: NSObject
@property (nonatomic) Node *nextNode;
@property (nonatomic) NSString *value;
@end

antrix1989

#import <Foundation/Foundation.h>

// Given a linked list, determine if it has a cycle in it.
// 1 -> 2 -> 3 -> 4

@interface Node: NSObject
@property (nonatomic) Node *nextNode;
@property (nonatomic) NSString *value;
@end

antrix1989

#import <Foundation/Foundation.h>

// Reverse a singly linked list.
// 1 -> 2 -> 3 -> 4

@interface Node: NSObject
@property (nonatomic) Node *nextNode;
@property (nonatomic) NSString *value;
@end

antrix1989

// Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.
// 1 -> 2 -> 3 -> 4

@interface Node: NSObject
@property (nonatomic) Node *nextNode;
@property (nonatomic) NSString *value;
@end

@implementation Node
@end

antrix1989

#import <Foundation/Foundation.h>

@interface NSString (ConvertToArray)
-(NSArray *)convertToArray;
@end

@implementation NSString (ConvertToArray)

-(NSArray *)convertToArray
{

antrix1989

// Implement strStr()
// O(n*m)

@interface NSString (ConvertToArray)
-(NSArray *)convertToArray;
@end

@implementation NSString (ConvertToArray)

-(NSArray *)convertToArray

antrix1989

#import <Foundation/Foundation.h>

// Anagram
// Given two strings s and t, write a function to determine if t is an anagram of s.
// 8:30 PM

@interface NSString (ConvertToArray)
-(NSArray *)convertToArray;
@end

antrix1989

// 3 Sum
// You may assume that each input would have exactly one solution, and you may not use the same element twice.

void print3sum(NSMutableArray *array, NSNumber *number)
{
    if (array.count < 3) return;
    
    for (int i = 0; i < array.count - 2; i++) { // 0
        int l = i + 1; // 1
        int r = array.count - 1;

antrix1989

#import <Foundation/Foundation.h>

// Two Sum
// You may assume that each input would have exactly one solution, and you may not use the same element twice.

void print2sum(NSMutableArray *array, NSNumber *number)
{
    if (array.count <= 1) return;
    
    int l = 0;