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# Problem AStopwatch

Robin just received a stopwatch from her grandfather. Robin’s stopwatch has a single button. Pressing the button alternates between stopping and starting the stopwatch’s timer. When the timer is on, the displayed time increases by 1 every second.

Initially the stopwatch is stopped and the timer reads 0 seconds. Given a sequence of times that the stopwatch button is pressed, determine what the stopwatch’s timer displays.

## Input

The first line of input contains a single integer $N$ ($1 \leq N \leq 1\, 000$), which is the number of times the stopwatch was pressed.

The next $N$ lines describe the times the stopwatch’s button was pressed in increasing order. Each line contains a single integer $t$ ($0 \leq t \leq 10^6$), which is the time the button was pressed. No two button presses happen on the same second.

## Output

Display still running if the stopwatch’s timer is still running after all button presses were made. Otherwise display the number of seconds displayed on the stopwatch’s timer.

Sample Input 1 Sample Output 1
2
7
11

4

Sample Input 2 Sample Output 2
5
2
5
9
10
17

still running

Sample Input 3 Sample Output 3
4
0
2
104
117

15

CPU Time limit 1 second
Memory limit 1024 MB