I just want to know, how to use the function "sum" effectively, returned in the following code.

distance is a structure.

Code:distance &sum(distance L1, distanceL2); distance L3; // global structure distance &sum(distance L1,distance L2) { L3.feet=L1.feet+L2.feet+(L1.inches+L2.inches)/12; L3.inches=(L1.inches+L2.inches)%12; return L3; }