Total hours a machine ran
A machine records operations as start and end minutes past midnight. Convert the whole running total into whole hours.
- Each operation adds end minus start minutes.
- Total is reported in whole hours, truncated down.
- Operations never cross midnight and every end is after its start.
runHours(operations: list<Operation>) → int
Go needs a compiler and Drill does not host one yet, so this page is the reference rather than an exercise: the problem, worked examples, and the solution in full. To type it out, the same problem runs in Python.
Where you start
func runHours(operations []Operation) int {
}Worked examples
| Call | Result |
|---|---|
runHours([]Operation{Operation{Start: 0, End: 60}, Operation{Start: 600, End: 900}}) | 6 |
runHours([]Operation{Operation{Start: 540, End: 600}}) | 1 |
runHours([]Operation{}) | 0 |
runHours([]Operation{Operation{Start: 0, End: 30}}) | 0 |
Hint
Sum the minute spans, then integer-divide the total by sixty.
Reference solution in Go
func runHours(operations []Operation) int {
total := 0
for _, o := range operations {
total += o.End - o.Start
}
return total / 60
}