--- a/src/synchronizedQueue/synchronizedQueue.c	Mon May 25 01:53:02 2015 +0900
+++ b/src/synchronizedQueue/synchronizedQueue.c	Tue Jun 02 14:17:07 2015 +0900
@@ -80,6 +80,8 @@
     context->data[Queue]->queue.count++;
     printf("Put %d\n\n", context->data[Queue]->queue.last->element.value);
 
+    // signal
+    pthread_cond_signal(&context->data[Queue]->queue.cond);
     // unlock
     pthread_mutex_unlock(&context->data[Queue]->queue.mutex);
     goto (context->code[next])(context);
@@ -121,17 +123,15 @@
 }
 
 __code meta_get(struct Context* context, enum Code next) {
-    if (context->data[Queue]->queue.count == 0) {
-        printf("queue is empty\n");
-        pthread_mutex_unlock(&context->data[Queue]->queue.mutex);
-        goto (context->code[next])(context);
-    } else {
-        printf("      Get %d\n\n", context->data[Queue]->queue.first->element.value);
-        context->data[Queue]->queue.first = (context->data[Queue]->queue.first->element.next) ? context->data[Queue]->queue.first->element.next : 0;
-        context->data[Queue]->queue.count--;
-        pthread_mutex_unlock(&context->data[Queue]->queue.mutex);
-        goto (context->code[next])(context);
+    // thread wait if queue is empty
+    while (context->data[Queue]->queue.count == 0) {
+        pthread_cond_wait(&context->data[Queue]->queue.cond, &context->data[Queue]->queue.mutex);
     }
+    printf("      Get %d\n\n", context->data[Queue]->queue.first->element.value);
+    context->data[Queue]->queue.first = (context->data[Queue]->queue.first->element.next) ? context->data[Queue]->queue.first->element.next : 0;
+    context->data[Queue]->queue.count--;
+    pthread_mutex_unlock(&context->data[Queue]->queue.mutex);
+    goto (context->code[next])(context);
 }
 
 __code get(struct Context* context) {

--- a/src/synchronizedQueue/synchronizedQueueContext.c	Mon May 25 01:53:02 2015 +0900
+++ b/src/synchronizedQueue/synchronizedQueueContext.c	Tue Jun 02 14:17:07 2015 +0900
@@ -49,6 +49,7 @@
     context->heap          += sizeof(struct Queue);
     context->data[Queue]->queue.first = 0;
     pthread_mutex_init(&context->data[Queue]->queue.mutex, NULL);
+    pthread_cond_init(&context->data[Queue]->queue.cond, NULL);
 
     context->dataNum = Queue;
 }

--- a/src/synchronizedQueue/synchronizedQueueContext.h	Mon May 25 01:53:02 2015 +0900
+++ b/src/synchronizedQueue/synchronizedQueueContext.h	Tue Jun 02 14:17:07 2015 +0900
@@ -44,6 +44,7 @@
         union Data* last;
         int   count;
         pthread_mutex_t mutex;
+        pthread_cond_t cond;
     } queue;
     struct Element {
         int value;

--- a/src/synchronizedQueue/synchronizedQueueForSemContext.c	Mon May 25 01:53:02 2015 +0900
+++ b/src/synchronizedQueue/synchronizedQueueForSemContext.c	Tue Jun 02 14:17:07 2015 +0900
@@ -24,20 +24,20 @@
     context->data       = malloc(sizeof(union Data*)*ALLOCATE_SIZE);
     context->heap_start = malloc(context->dataSize);
 
-    context->codeNum         = Exit;
-    context->code[Code1]     = code1;
-    context->code[Code2]     = code2;
-    context->code[Code3]     = code3;
-    context->code[Code4]     = code4;
-    context->code[Code5]     = code5;
-    context->code[Code6]     = code6;
-    context->code[Code7]     = code7;
-    context->code[Allocator] = allocate;
-    context->code[Sender]    = sender;
-    context->code[Put]       = put;
-    context->code[Receiver]  = receiver;
-    context->code[Get]       = get;
-    context->code[Exit]      = exit_code;
+    context->codeNum          = Exit;
+    context->code[Code1]      = code1;
+    context->code[Code2]      = code2;
+    context->code[Code3]      = code3;
+    context->code[Code4]      = code4;
+    context->code[Code5]      = code5;
+    context->code[Code6]      = code6;
+    context->code[Code7]      = code7;
+    context->code[Allocator]  = allocate;
+    context->code[Sender]     = sender;
+    context->code[Put]        = put;
+    context->code[Receiver]   = receiver;
+    context->code[Get]        = get;
+    context->code[Exit]       = exit_code;
     context->code[ThreadExit] = thread_exit;
 
     context->heap = context->heap_start;