maps stl

1#include <bits/stdc++.h>
2#include <iostream>
3#include <map>
4using namespace std;
5void mapDemo(){
6	map<int, int> A;
7	A[1] = 100;
8	A[2] = -1;
9	A[3] = 200;
10	A[100000232] = 1;
11	//to find the value of a key
12	//A.find(key)
13	
14	//to delete the key
15	//A.erase(key)
16	
17	map<char, int> cnt;
18	string x = "Sumant Tirkey";
19	
20	for(char c:x){
21		cnt[c]++;//map the individual character with it's occurance_Xtimes
22	}
23	
24	//see  how many times a and z occures in my name
25	cout<< cnt['a']<<" "<<cnt['z']<<endl;
26	
27} 
28	
29int main() {
30	mapDemo();
31	return 0;
32}

1#include<iostream>
2#include<map>
3#include<algorithm>
4
5using namespace std;
6
7int main()
8{
9    map<int,int>map1{{1,2},{2,3},{3,5},{4,7},{5,11}};
10    cout<<map1.at(3)<<endl;
11    cout<<map1[3]<<endl;
12    map1[6];
13    for(map<int,int>::iterator it=map1.begin();it!=map1.end();it++)
14    {
15        cout<<it->first<<" "<<it->second<<endl;
16    }
17    cout<<endl;
18    cout<<"----------------------"<<endl;
19    map1.insert(pair<int,int>(7,17));
20    map1.insert(make_pair(8,23));
21
22    for(map<int,int>::iterator it=map1.begin();it!=map1.end();it++)
23    {
24        cout<<it->first<<" "<<it->second<<endl;
25    }
26    cout<<endl;
27    map<int,int>::iterator its=map1.find(2);
28    map1.erase(its);
29    for(map<int,int>::iterator it=map1.begin();it!=map1.end();it++)
30    {
31        cout<<it->first<<" "<<it->second<<endl;
32    }
33    cout<<endl;
34    auto itss=map1.begin();
35    auto itss2=map1.end();
36    map1.erase(itss,itss2);
37    for(map<int,int>::iterator it=map1.begin();it!=map1.end();it++)
38    {
39        cout<<it->first<<" "<<it->second<<endl;
40    }
41    cout<<endl;
42
43    return 0;
44}
45