You are given an old touch smartphone numbers having dial pad and calculator app.
The goal is to type a number on dial-pad.
Calculator have 1-9 and +, -, * , /, = as operations. But as the phone is old, some of the numbers and some operations can’t be touched.
But you can always make a number using other numbers and operations. There could be multiple ways of making a number. You have to find minimum operation for making a number.
For ex: let’s say 1,4,6,7,8,9 works and +,-,* works.
2,3,5 and / doesn’t work.
If you have to type 18-> 2 operations. (Each touch is considered an operation).
If you have to type 5 → ‘1+4=’ that requires 4 operations. There could be other ways to make ‘5’.
The goal is to find minimum operations.
Link to the question: You are given an old touch sma | CareerCup
Please help me in understanding the approach. Thank you