You are given a string S consisting of N characters. The string is a valid phone number if it consists of three segments of digits $($each three digits long$)$ separated by sing dashes. Write a function: bool solution$($string &$5)$; that, given a string S of length N$,$ returns true if the string S represents a valid phone number and false if it doesn't. Examples: $1.$ Given string S$="123-123-123",$ the function should return true. $2.$ Given string S$123123123",$ the function should return false, because the segments are separated by spaces instead of dashes. $03.$ Given string S$="123-123-1234",$ the function should return false, because there are too many digits in the last segment. $4.$ Given string S$001-501-511",$ the function should return