Mega Code Archive
Determine the lexicographical relationship between two maps
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#include <iostream>
#include <string>
#include <map>
using namespace std;
void show(const char *msg, map<string, int> mp);
int main() {
map<string, int> m;
m.insert(pair<string, int>("A", 100));
m.insert(pair<string, int>("G", 300));
m.insert(pair<string, int>("B", 200));
// Declare an iterator to a map<string, int>.
map<string, int>::iterator itr;
// Create another map that is the same as the first.
map<string, int> m2(m);
show("Contents of m2: ", m2);
if(m < m2) cout << "m is less than m2." << endl;
// Remove the Beta from m.
m.erase("Beta");
show("m after removing Beta: ", m);
if(m > m2)
cout << "Now, m is greater than m2." << endl;
return 0;
}
// Display the contents of a map<string, int> by using an iterator.
void show(const char *msg, map<string, int> mp) {
map<string, int>::iterator itr;
cout << msg << endl;
for(itr=mp.begin(); itr != mp.end(); ++itr)
cout << " " << itr->first << ", " << itr->second << endl;
cout << endl;
}
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