map_in_c++

//
//  main.cpp
//
//  Created by Prince  Kumar on 30/04/2020.
//  Copyright © 2020 Prince  Kumar. All rights reserved.
//
//                      ---** MAP in C++ **---

#include <iostream>
#include <map>
using namespace std;
int main(){
    // roll_num   weight of student
    map < int , int > person;
    
    // Insert the values in map
    person.insert(pair<int, int>(1,35));
    person.insert({2, 40});
    person.insert({3,50});
    person.insert({5, 10});
    
    
//    auto it = person.find(3);
//    person.erase(it);
    
    //person.erase(5);
    
    
    // print
    for(auto itr = person.begin() ; itr!=person.end() ; ++itr){
        cout<<itr->first <<"  " <<itr->second<<endl;
    }
    
    // .begin()  --> return iterator
    //auto var  = person.begin();
    //cout<<"By var iterator  " <<var->first <<" "<<var->second<<endl;
    
    // .end()  --> return iterator
    //auto var  = person.end();   // Not actual map
    //cout<<"By var iterator  " <<var->first <<" "<<var->second<<endl;
    
    //cout<<person.size()<<endl;
    //cout<<person.max_size()<<endl;
    
    // .erase()
    
    // .empty()  -->whether map is empty or not
    // 0 --> map is not empty
    // 1 --> map is empty
    
    
    person.clear();   // delete all the values in map
    cout<<"map is empty or not ?  "<<person.empty()<<endl;
    
    
    
   
}