(Solved): Given a string S with length N that contains numbers, lowercase characters, and '-', you are requir ...

Given a string $S$ with length $N$ that contains numbers, lowercase characters, and '-', you are required to sum all the substrings that can be converted to a number. For example, if we let $S=$ "12a-a-53-1", then all substrings that can be converted to a number will be "1", "12", "2", "-5", "-53", "5", "53", "3", "-1", "1". The summation of all valid substrings is $1+12+2+(?5)+(?53)+5+53+3+(?1)+1=18$. You should complete the function as follows. Note: don't change the function format and only add code inside the function block. Case 1: $S="12a?a?53?1"$. In this case, the function should return 18. Case 2: $S=$ "1a12-11-". In this case, the function should return 17. def , sum_str $(\mathrm{S}):$ S: a string return a number ans pass sum_str ("12a-a-53-1") def sum_str(S): S: a string return a number ans pass sum_str ("12a-a-53-1")