#D10780. Test
Test
Test
problem
students will be tested in a classroom with seats in a straight line. Seats are numbered from the front, and per seat can seat students.
Now each student is sitting in the seats.
To start the test, the following conditions must be met:
- students are sitting in every seat.
Therefore, we decided to repeat the following operations until the conditions were met.
- Move the student sitting at the back and sit at the front of the vacant seats.
Find the number of operations required to meet the conditions.
output
Output the number of operations required to meet the conditions. Also, output a line break at the end.
Example
Input
6 4 1 4 5 6
Output
2
inputFormat
outputFormat
output
Output the number of operations required to meet the conditions. Also, output a line break at the end.
Example
Input
6 4 1 4 5 6
Output
2
样例
6 4
1 4 5 6
2