Unordered_map with pair as key not working

[kathuria (NAMAN KATHURIA)]

my code https://ide.codingblocks.com/s/43368

[Abhishek-Vanjani-1385688111468238 (Abhishek Vanjani)]

You can refer this article :https://stackoverflow.com/questions/32685540/unordered-map-with-pair-as-key-not-compiling