Add Program for unordered_map of pairs in C++

[DoraemonMS-903]

Input :
Enter the number of houses that he visited today :5
Enter the coordinate of HouseNo. 1 :1000 12985
Enter the coordinate of HouseNo. 2 :12548 25621
Enter the coordinate of HouseNo. 3 :14586 26481
Enter the coordinate of HouseNo. 4 :12 63
Enter the coordinate of HouseNo. 5 :14689 36945
Output :
Houses that he visited today:
12 63
14689 36945
14586 26481
1000 12985
12548 25621