diff --git a/grow/defs/add_one.yaml b/grow/defs/add_one.yaml
index 2936eca..f155a13 100644
--- a/grow/defs/add_one.yaml
+++ b/grow/defs/add_one.yaml
@@ -2,15 +2,11 @@ global_memory_size: 1
 function_memory_size: 1
 instruction_limit: 2
 samples:
-- global_memory_inputs:
-    0: 0
-  global_memory_outputs:
-    0: 1
-- global_memory_inputs:
-    0: 1
-  global_memory_outputs:
-    0: 2
-- global_memory_inputs:
-    0: 100
-  global_memory_outputs:
-    0: 101
+- in:  [0]
+  out: [1]
+
+- in:  [1]
+  out: [2]
+
+- in:  [100]
+  out: [101]
diff --git a/grow/defs/mul_five.yaml b/grow/defs/mul_five.yaml
index e824f7d..bb97b0d 100644
--- a/grow/defs/mul_five.yaml
+++ b/grow/defs/mul_five.yaml
@@ -2,19 +2,14 @@ global_memory_size: 1
 function_memory_size: 1
 instruction_limit: 2
 samples:
-- global_memory_inputs:
-    0: 0
-  global_memory_outputs:
-    0: 0
-- global_memory_inputs:
-    0: 1
-  global_memory_outputs:
-    0: 5
-- global_memory_inputs:
-    0: 2
-  global_memory_outputs:
-    0: 10
-- global_memory_inputs:
-    0: 100
-  global_memory_outputs:
-    0: 500
+- in:  [0]
+  out: [0]
+
+- in:  [1]
+  out: [5]
+
+- in:  [2]
+  out: [10]
+
+- in:  [100]
+  out: [500]
diff --git a/grow/defs/mul_four.yaml b/grow/defs/mul_four.yaml
index 75794c0..b3c048e 100644
--- a/grow/defs/mul_four.yaml
+++ b/grow/defs/mul_four.yaml
@@ -2,19 +2,14 @@ global_memory_size: 1
 function_memory_size: 1
 instruction_limit: 2
 samples:
-- global_memory_inputs:
-    0: 0
-  global_memory_outputs:
-    0: 0
-- global_memory_inputs:
-    0: 1
-  global_memory_outputs:
-    0: 4
-- global_memory_inputs:
-    0: 2
-  global_memory_outputs:
-    0: 8
-- global_memory_inputs:
-    0: 100
-  global_memory_outputs:
-    0: 400
+- in:  [0]
+  out: [0]
+
+- in:  [1]
+  out: [4]
+
+- in:  [2]
+  out: [8]
+
+- in:  [100]
+  out: [400]
diff --git a/grow/defs/mul_two.yaml b/grow/defs/mul_two.yaml
index f6d39cf..4d97be7 100644
--- a/grow/defs/mul_two.yaml
+++ b/grow/defs/mul_two.yaml
@@ -2,19 +2,14 @@ global_memory_size: 1
 function_memory_size: 1
 instruction_limit: 2
 samples:
-- global_memory_inputs:
-    0: 0
-  global_memory_outputs:
-    0: 0
-- global_memory_inputs:
-    0: 1
-  global_memory_outputs:
-    0: 2
-- global_memory_inputs:
-    0: 2
-  global_memory_outputs:
-    0: 4
-- global_memory_inputs:
-    0: 100
-  global_memory_outputs:
-    0: 200
+- in:  [0]
+  out: [0]
+
+- in:  [1]
+  out: [2]
+
+- in:  [2]
+  out: [4]
+
+- in:  [100]
+  out: [200]
diff --git a/grow/sample.go b/grow/sample.go
index cf51e47..7aec5b9 100644
--- a/grow/sample.go
+++ b/grow/sample.go
@@ -3,19 +3,19 @@ package grow
 import "github.com/firestuff/subcoding/vm"
 
 type Sample struct {
-	GlobalMemoryInputs  map[uint64]uint64 `yaml:"global_memory_inputs"`
-	GlobalMemoryOutputs map[uint64]uint64 `yaml:"global_memory_outputs"`
+	In  []uint64 `yaml:"in,flow"`
+	Out []uint64 `yaml:"out,flow"`
 }
 
 func (s *Sample) SetInputs(state *vm.State) {
-	for i, val := range s.GlobalMemoryInputs {
-		state.GlobalMemory().WriteUnsigned(i, val)
+	for i, val := range s.In {
+		state.GlobalMemory().WriteUnsigned(uint64(i), val)
 	}
 }
 
 func (s *Sample) OutputsMatch(state *vm.State) bool {
-	for i, val := range s.GlobalMemoryOutputs {
-		if state.GlobalMemory().MustReadUnsigned(i) != val {
+	for i, val := range s.Out {
+		if state.GlobalMemory().MustReadUnsigned(uint64(i)) != val {
 			return false
 		}
 	}