GlobeX Cup '18 S5 - Math Bash
View as PDFYou are taking your calculus exam. In the exam room, there is an  grid of desks, each with exactly one student taking an exam at that desk.
Your teacher has come up with an interesting way of grading the exams. Let  represent the initial mark that the student at position 
 got on the exam. His actual mark, 
, is equal to 
 where 
 is the number of students who have an actual mark higher than or equal to student 
's initial mark and their position is 
 where 
 and 
. Formally, 
 is the number of students where 
 and 
.
Wanting to know how much everyone's marks change, you are to find the sum of  for all 
 
.
Input Specification
The first line will contain the  
.
The next line will contain  lines will each contain 
 space-separated integers 
 
.
Output Specification
Output the sum of all , as defined above.
Sample Input 1
2
2 1
1 2
Sample Output 1
1
Explanation for Sample 1
Only the student at position  will have their mark changed. All other students will keep their current mark. Thus, 
, and 
. The student at position 
 will have their marks changed by one due to 
 
. The sum of all 
 is therefore one.
Sample Input 2
5
1 4 2 5 3
5 2 8 4 2
1 1 1 1 3
9 9 2 3 1
1 1 1 1 1
Sample Output 2
82
Sample Input 3
10
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
10 9 8 7 6 5 4 3 2 1
10 9 8 7 6 5 4 3 2 1
1 2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
10 9 8 7 6 5 4 3 2 1
10 9 8 7 6 5 4 3 2 1
10 9 8 7 6 1 2 3 4 5
10 9 8 7 6 1 2 3 4 5
Sample Output 3
1420
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