From d769c89103ea2d03047c879039f7623623605897 Mon Sep 17 00:00:00 2001
From: oysheng <33340252+oysheng@users.noreply.github.com>
Date: Mon, 15 Oct 2018 15:54:30 +0800
Subject: [PATCH] fix the operation for binary operator with the same variable
 (#16)

---
 compiler/compile.go |  4 +++-
 compiler/stack.go   | 42 ++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/compiler/compile.go b/compiler/compile.go
index c3d277f..7145274 100644
--- a/compiler/compile.go
+++ b/compiler/compile.go
@@ -498,7 +498,9 @@ func compileStatement(b *builder, stk stack, contract *Contract, env *environ, c
 		}
 
 		// restore the defined variable counts
-		counts[stmt.variable.Name] = varCount
+		if tmpCounts[stmt.variable.Name] > 0 {
+			counts[stmt.variable.Name] = varCount
+		}
 
 		// modify stack name
 		stk.str = stmt.variable.Name
diff --git a/compiler/stack.go b/compiler/stack.go
index 1459f02..c86e2b6 100644
--- a/compiler/stack.go
+++ b/compiler/stack.go
@@ -52,20 +52,58 @@ func (stk stack) dropN(n int) stack {
 	return stk
 }
 
-func (stk stack) find(str string) int {
+func (stk stack) recurFind(str string) int {
 	if stk.isEmpty() {
 		return -1
 	}
 	if stk.str == str {
 		return 0
 	}
-	res := stk.drop().find(str)
+	res := stk.drop().recurFind(str)
 	if res < 0 {
 		return res
 	}
 	return res + 1
 }
 
+func (stk stack) count() map[string]int {
+	if stk.isEmpty() {
+		return nil
+	}
+	stackCounts := make(map[string]int)
+	for {
+		stackCounts[stk.str]++
+		stk = stack{stk.prev}
+		if stk.stackEntry == nil {
+			break
+		}
+	}
+	return stackCounts
+}
+
+func (stk stack) find(str string) int {
+	stackCounts := stk.count()
+	if stk.isEmpty() || stackCounts[str] == 0 {
+		return -1
+	}
+
+	var pos int
+	for {
+		if stk.str == str {
+			if stackCounts[str] == 1 {
+				break
+			}
+			stackCounts[str]--
+		}
+		stk = stack{stk.prev}
+		if stk.stackEntry == nil {
+			break
+		}
+		pos++
+	}
+	return pos
+}
+
 func (stk stack) roll(n int) stack {
 	var x func(stack, int) (stack, string)
 	x = func(stk stack, n int) (stack, string) {
-- 
2.11.0