fix 2 bugs

main.go

@@ -230,9 +230,6 @@ func Choose(cumulativeScore int, depth int, fromDepth int) (int, bool) {
 	if c == nil {
 		// At this point we have a complete configuration
 		fmt.Printf("score obtained: %d depth: %d\n", cumulativeScore, depth)
-		// INVESTIGATE HERE : why do we have different scores ???
-		// when we're only asking to fix 22 down in the stack
-		return 8270, true
 		if cumulativeScore >= bestTotalScore {
 			bestTotalScore = cumulativeScore
 			// Go back to random depth and make a new change
@@ -246,9 +243,6 @@ func Choose(cumulativeScore int, depth int, fromDepth int) (int, bool) {
 	var rdepth int
 	var fix bool
 	r := c.pickBestRide()
-	// if depth >= 252 && depth <= 258 {
-	// 	fmt.Printf("yo picking id %d score %d c=%+v\n", r.ID, cumulativeScore, c)
-	// }
 	if r != nil {
 		rdepth, fix = c.AssignRideRecur(r, cumulativeScore, depth, fromDepth)
 		// if depth == reverse depth, make a change
@@ -257,10 +251,8 @@ func Choose(cumulativeScore int, depth int, fromDepth int) (int, bool) {
 			var r *Ride
 			if fix {
 				r = c.pickBestRide()
-				fmt.Printf("pickBestRide id %d depth %d\n", r.ID, depth)
 			} else {
 				r = c.pickRandomRide()
-				fmt.Printf("pickRandomRide id %d depth %d\n", r.ID, depth)
 			}
 			// note fromDepth reset to depth
 			rdepth, fix = c.AssignRideRecur(r, cumulativeScore, depth, depth)
@@ -364,6 +356,13 @@ type prioq struct {
 	bintree []*Car
 }
 
+func (c *Car) greater(c2 *Car) bool {
+	if c.Arrival == c2.Arrival {
+		return c.ID > c2.ID
+	}
+	return c.Arrival > c2.Arrival
+}
+
 func (pq *prioq) Add(car *Car) {
 	pq.bintree = append(pq.bintree, car)
 	pq.bintree[len(pq.bintree)-1].pqindex = len(pq.bintree) - 1
@@ -371,7 +370,7 @@ func (pq *prioq) Add(car *Car) {
 	// Rebalance tree to respect invariant
 	var i = len(pq.bintree) - 1
 	var p = (i - 1) / 2
-	for p >= 0 && pq.bintree[p].Arrival > pq.bintree[i].Arrival {
+	for p >= 0 && pq.bintree[p].greater(pq.bintree[i]) {
 		pq.bintree[p], pq.bintree[i] = pq.bintree[i], pq.bintree[p]
 		pq.bintree[p].pqindex = p
 		pq.bintree[i].pqindex = i
@@ -380,22 +379,22 @@ func (pq *prioq) Add(car *Car) {
 	}
 }
 
-func (pq *prioq) RemoveAtIndex(k int) *Car {
+func (pq *prioq) Pop() *Car {
 	if len(pq.bintree) == 0 {
 		return nil
 	}
 
-	if k == len(pq.bintree)-1 {
-		elem := pq.bintree[k]
-		pq.bintree = pq.bintree[:k]
+	if len(pq.bintree) == 1 {
+		elem := pq.bintree[0]
+		pq.bintree = pq.bintree[:0]
 		return elem
 	}
 
-	pq.bintree[k].pqindex = -1
-	elem := pq.bintree[k]
-	// Put last element at hole
-	pq.bintree[k] = pq.bintree[len(pq.bintree)-1]
-	pq.bintree[k].pqindex = k
+	pq.bintree[0].pqindex = -1
+	elem := pq.bintree[0]
+	// Put last element at root
+	pq.bintree[0] = pq.bintree[len(pq.bintree)-1]
+	pq.bintree[0].pqindex = 0
 	// Remove last element
 	pq.bintree = pq.bintree[:len(pq.bintree)-1]
 
@@ -406,14 +405,13 @@ func (pq *prioq) RemoveAtIndex(k int) *Car {
 
 	// Rebalance tree to respect invariant
 	len := len(pq.bintree)
-	i := k
-	left, right := 0, 0
+	i, left, right := 0, 0, 0
 	for {
 		left = 2*i + 1
 		right = 2*i + 2
 		if left < len && right < len { // Two children
-			if pq.bintree[left].Arrival <= pq.bintree[right].Arrival {
-				if pq.bintree[i].Arrival <= pq.bintree[left].Arrival {
+			if !pq.bintree[left].greater(pq.bintree[right]) {
+				if !pq.bintree[i].greater(pq.bintree[left]) {
 					break // Inferior to both children
 				} else {
 					pq.bintree[i], pq.bintree[left] = pq.bintree[left], pq.bintree[i]
@@ -422,7 +420,7 @@ func (pq *prioq) RemoveAtIndex(k int) *Car {
 					i = left
 				}
 			} else {
-				if pq.bintree[i].Arrival <= pq.bintree[right].Arrival {
+				if !pq.bintree[i].greater(pq.bintree[right]) {
 					break // Inferior to both children
 				} else {
 					pq.bintree[i], pq.bintree[right] = pq.bintree[right], pq.bintree[i]
@@ -432,7 +430,7 @@ func (pq *prioq) RemoveAtIndex(k int) *Car {
 				}
 			}
 		} else if left < len { // One child (left)
-			if pq.bintree[i].Arrival <= pq.bintree[left].Arrival {
+			if !pq.bintree[i].greater(pq.bintree[left]) {
 				break // Inferior to only child
 			}
 			pq.bintree[i], pq.bintree[left] = pq.bintree[left], pq.bintree[i]
@@ -448,8 +446,18 @@ func (pq *prioq) RemoveAtIndex(k int) *Car {
 	return elem
 }
 
-func (pq *prioq) Pop() *Car {
-	return pq.RemoveAtIndex(0)
+func (pq *prioq) RemoveAtIndex(k int) *Car {
+	if k == 0 {
+		return pq.Pop()
+	}
+	pq.bintree[k].pqindex = -1
+	elem := pq.bintree[k]
+	reassign := pq.bintree[k+1:]
+	pq.bintree = pq.bintree[:k]
+	for _, c := range reassign {
+		pq.Add(c)
+	}
+	return elem
 }
 
 func (pq *prioq) empty() bool {