For example I have following string, which will be given as input from a user:
string str = "0-00:03"
Inside my contract I would like to check that:
- str should be "-"
- str should be ":"
- and the remaining characters have to be numeric value.
This operation is easy to do C where with pointer I can iterate each character and check its char value. But I was not able to operate this inside my contract under Solidity language.