Finding list of strings that is an intersection of given 2 lists.

Given two lists of strings return a list of strings that is an intersection of both of the lists.
Analyze running time and space complexity.
Give Test Case scenarios.

complexity is O(m+n) where m and n are size of list 1 and list 2
#include<iostream>
#include<map>
#include<string.h>
#include<set>
using namespace std;

int main(){
string list1[]={“hello”,
“hi”,
“cool”,
“vishnu”};
string list2[]={“awesome”,
“code”,
“hello”,
“hi”,
“cool”};
map<string,bool> m;
set<string> list3;
for(int i=0;i<4;i++)
m[list1[i]]=true;
for(int i=0;i<5;i++)
if(m[list2[i]]==true)
list3.insert(list2[i]);
set<string>::iterator it;
for(it=list3.begin();it!=list3.end();it++)
cout<<*it<<endl;

}