map count function c 2b 2b

1map_name.count(key k)
2/*
3   Parameters: k which specifies the key to be searched in the map container.
4   Return Value: returns the number of times the key K is present in the map container. 
5   		  "RETURNS 0"- if the key is not present in the map container.
6*/

1int n; cin>>n;
2long val;
3map<int,long> mp3;
4long long res=0;
5while(n--){
6	cin>>val;
7	if(mp3.count(val)) 	res+=mp3[val]; 
8    //mp3.count(val) returns 1 if val is present in the map already or 
9    //the number of times the key K is present in the map container.
10    if(mp2.count(val)) 	mp3[val*r]+=mp2[val];
11	mp2[val*r]++;
12}
13cout<<res<<endl;