Consider the following prototype of the C$++$ function that computes and returns the sum of all digits in the decimal representation of an integer value m$.$ int sumOfDigits$($int m$)$; For example, the sum of digits in $1234$ is $1+2+3+4=10.$ That means, if the input to the function is $1234,$ the function returns $10.$ Similarly, if the input to the function is $-1234,$ the function returns $-10.$ Implement the function in C$++$