Add a mean to get an index, allowing iterations of the queue.
Antoine Grondin
9 years ago
| 58 | 58 |
return q.buf[q.head]
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| 59 | 59 |
}
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| 60 | 60 |
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61 |
// Get returns the element at index i in the queue. If the index is invalid, the
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// call will panic.
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func (q *Queue) Get(i int) interface{} {
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64 |
if i >= q.Length() || i < 0 {
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panic("index out of range")
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}
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modi := (q.head + i) % len(q.buf)
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return q.buf[modi]
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}
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| 61 | 71 |
// Remove removes the element from the front of the queue. If you actually want the element,
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| 62 | 72 |
// call Peek first. If the queue is empty (Length == 0), Remove will put the queue in a bad
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| 63 | 73 |
// state and all further operations will be undefined.
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| 11 | 11 |
for i := 0; i < 1000; i++ {
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| 12 | 12 |
q.Add(i)
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| 13 | 13 |
if q.Length() != i+1 {
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| 14 | |
t.Error("adding: queue with", i , "elements has length", q.Length())
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14 |
t.Error("adding: queue with", i, "elements has length", q.Length())
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| 15 | 15 |
}
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| 16 | 16 |
}
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| 17 | 17 |
for i := 0; i < 1000; i++ {
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| 18 | 18 |
q.Remove()
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| 19 | 19 |
if q.Length() != 1000-i-1 {
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| 20 | |
t.Error("removing: queue with", 1000-i-i , "elements has length", q.Length())
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t.Error("removing: queue with", 1000-i-i, "elements has length", q.Length())
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| 21 | 21 |
}
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| 22 | 22 |
}
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23 |
}
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24 |
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func TestQueueGet(t *testing.T) {
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q := New()
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for i := 0; i < 1000; i++ {
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q.Add(i)
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for j := 0; j < q.Length(); j++ {
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if q.Get(j).(int) != j {
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t.Errorf("index %d doesn't contain %d", j, j)
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}
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}
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}
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}
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func TestQueueGetOutOfRangePanics(t *testing.T) {
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q := New()
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40 |
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q.Add(1)
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q.Add(2)
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q.Add(3)
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func() {
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defer func() {
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if r := recover(); r == nil {
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t.Errorf("should panic when negative index")
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} else {
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t.Logf("got panic as expected: %v", r)
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}
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}()
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func() {
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q.Get(-1)
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}()
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}()
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func() {
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defer func() {
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if r := recover(); r == nil {
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t.Errorf("should panic when index greater than length")
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} else {
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t.Logf("got panic as expected: %v", r)
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}
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}()
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func() {
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q.Get(4)
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}()
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}()
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| 23 | 72 |
}
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| 24 | 73 |
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| 25 | 74 |
// General warning: Go's benchmark utility (go test -bench .) increases the number of
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