Group Totals

Have the function GroupTotals(strArr) read in the strArr parameter containing key:value pairs where the key is a string and the value is an integer. Your program should return a string with new key:value pairs separated by a comma such that each key appears only once with the total values summed up.

For example: if strArr is ["B:-1", "A:1", "B:3", "A:5"] then your program should return the string A:6,B:2.

Your final output string should return the keys in alphabetical order. Exclude keys that have a value of 0 after being summed up.

Examples

Input: ["X:-1", "Y:1", "X:-4", "B:3", "X:5"]
Output: B:3,Y:1

Input: ["Z:0", "A:-1"]
Output: A:-1