Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Lock & Key problem using Hash-map
A list of different locks and another list of keys are given. Our task is to find the correct match of lock and key from the given list, and assign that key with the lock when it is correct.
In this approach we will traverse all of the locks and create a hash-map, after that, each key is searched in the hash-map. When the key is matches, then that is marked as a valid key and assigned with a lock.
Input and Output
Input:
The lists of locks and keys.
lock = { ),@,*,^,(,%, !,$,&,#}
key = { !, (, #, %, ), ^, &, *, $, @ }
Output:
After matching Locks and Keys:
Locks: ! ( # % ) ^ & * $ @
Keys: ! ( # % ) ^ & * $ @Algorithm
lockAndKeyProblem(lock, key, n)
Input: The list of locks, the list of keys, n.
Output: Find which key is for which lock.
Begin define hashmap for i in range (0 to n-1), do hashmap[lock[i]] := i //set hashmap for locks done for i in range (0 to n-1), do if key[i] is found in the hashmap, then lock[i] = key[i] done End
Example
#include<iostream>
#include<map>
using namespace std;
void show(char array[], int n) {
for(int i = 0; i<n; i++)
cout << array[i] << " ";
}
void lockAndKeyProblem(char lock[], char key[], int n) {
map<char, int> hashMap;
for(int i = 0; i<n; i++)
hashMap[lock[i]] = i; //hash map for locks
for(int i = 0; i<n; i++) //for each keys for each lock
if(hashMap.find(key[i]) != hashMap.end()) {
lock[i] = key[i];
}
}
int main() {
char lock[] = {')','@','*','^','(','%','!','$','&','#'};
char key[] = {'!','(','#','%',')','^','&','*','$','@'};
int n = 10;
lockAndKeyProblem(lock, key, n);
cout << "After matching Locks and Keys:"<<endl;
cout << "Locks: "; show(lock, n); cout << endl;
cout << "Keys: "; show(key, n); cout << endl;
}Output
After matching Locks and Keys: Locks: ! ( # % ) ^ & * $ @ Keys: ! ( # % ) ^ & * $ @
Updated on: 17-Jun-2020
602 Views
Advertisements