--- a/parallel_processing/ppb_data_shared/ppb_data_shared.cc	Fri Jan 03 02:03:11 2014 +0900
+++ b/parallel_processing/ppb_data_shared/ppb_data_shared.cc	Fri Jan 03 21:09:01 2014 +0900
@@ -3,21 +3,26 @@
 
 #define THREAD_NUM 2
 #define DATA_NUM 10
-#define SPLIT_DATA_NUM (DATA_NUM / THREAD_NUM)
 
 typedef struct _thread_arg {
     int thread_no;
     int *data;
+    pthread_mutex_t *mutex;
 } thread_arg_t;
 
 void *
 thread_func(void *arg)
 {
     thread_arg_t *targ = (thread_arg_t *)arg;
+    int result;
 
-    for (int i = 0; i < SPLIT_DATA_NUM; i++) {
-        printf("thread%d : %d + 1 = %d\n",
-            targ->thread_no, targ->data[i], targ->data[i] + 1);
+    /* starting mutex and ending mutex*/
+    for (int i = 0; i < DATA_NUM; i++) {
+        pthread_mutex_lock(targ->mutex);
+        result = targ->data[i] + 1;
+        sched_yield();
+        targ->data[i] = result;
+        pthread_mutex_unlock(targ->mutex);
     }
     return 0;
 }
@@ -29,21 +34,29 @@
     thread_arg_t targ[THREAD_NUM];
     int data[DATA_NUM];
     int i;
+    pthread_mutex_t mutex;
 
     /* initialize */
-    for (i = 0; i < DATA_NUM; i++) data[i] = i;
+    for (i = 0; i < DATA_NUM; i++) data[i] = 0;
+
+    /* initialized mutex*/
+    pthread_mutex_init(&mutex, NULL);
 
     /* spawn thread a number of THREAD_NUM */
     for (i = 0; i < THREAD_NUM; i++) {
         targ[i].thread_no = i;
+        targ[i].data = data;
+        targ[i].mutex = &mutex;
 
-        /* divide a data into THREAD_NUM*/
-        targ[i].data = &data[SPLIT_DATA_NUM * i];
         /* spawn thread*/
         pthread_create(&handle[i], NULL, &thread_func, (void*)&targ[i]);
     }
 
     /* wait for running all thread */
     for (i = 0; i < THREAD_NUM; i++) pthread_join(handle[i], NULL);
+
+    pthread_mutex_destroy(&mutex);
+
+    for (i = 0; i < DATA_NUM; i++) printf("data%d : %d\n", i, data[i]);
     return 0;
 }