EIU Programming Practices and Exams

Khanh is asking for your help in calculating his total credits. He gives you the list of courses and numbers of credits of each course and the list of grades for each course.

Only courses with grade larger than or equal to 50 are counted. Khanh needs to know how many credits he gained

Input

-      The first line contains one integer N - the number of courses to be calculated.

-      The N next lines each contains a string S and an integer c where S is the ID of the course and c is the number of credits of that course.

-      Each line in the last N lines contains an integer G and a string S where G is the grade of course S.

Output

Print out only one line containing the total number of credits that Khanh gained.

Sample