Each worker got his salary some times in a year. Print surnames of the workers with their final salary at the end of the year in increasing order of surname.
Each line contains information about worker: surname and his salary. The same employee may appear in the list several times - this means that he received his salary several times.
Print the surnames and salaries of all employees for the entire year in ascending order of surnames. That is, for each surname, print the total salary that he received during the year.