hello ! I was solving this problem from Codechef

I think that the solution on the editorial is wrong and it should fail this exemple :

6 6

1 3 1

1 2 1

2 4 1

3 5 2

4 5 2

4 6 3

the answer is 33 while the tester's algorithm output 34

Am I wrong ?

EDIT : you can find the tester's solution at the end of the Editorial