when to use a map c++ code example
Example 1: map in c++
#include <bits/stdc++.h>
#include <iostream>
#include <map>
using namespace std;
void mapDemo(){
map<int, int> A;
A[1] = 100;
A[2] = -1;
A[3] = 200;
A[100000232] = 1;
//to find the value of a key
//A.find(key)
//to delete the key
//A.erase(key)
map<char, int> cnt;
string x = "Sumant Tirkey";
for(char c:x){
cnt[c]++;//map the individual character with it's occurance_Xtimes
}
//see how many times a and z occures in my name
cout<< cnt['a']<<" "<<cnt['z']<<endl;
}
int main() {
mapDemo();
return 0;
}
Example 2: map of maps c++
map <typename,map<typename,typename>> mp;
map[key1][key2]=values