From 924b8fbde7261e2314879e03bf3eb6eb02714136 Mon Sep 17 00:00:00 2001
From: shencanhui <shencanhui@foxmail.com>
Date: Mon, 18 Apr 2016 19:35:16 +0800
Subject: [PATCH 1/6] =?UTF-8?q?=E4=BD=9C=E4=B8=9Aadduser=E4=BF=AE=E6=94=B9?=
 =?UTF-8?q?=E5=AE=8C=E6=88=90=20=E6=8F=90=E4=BA=A4=EF=BC=88=E6=B2=88?=
 =?UTF-8?q?=E7=81=BF=E8=BE=8921620142202663=EF=BC=89?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 assignments/shell/AddUsers/addUsers.sh  | 43 ++++++++++++++++++++-----
 assignments/shell/AddUsers/addUsers.sh~ | 36 +++++++++++++++++++++
 2 files changed, 71 insertions(+), 8 deletions(-)
 create mode 100644 assignments/shell/AddUsers/addUsers.sh~

diff --git a/assignments/shell/AddUsers/addUsers.sh b/assignments/shell/AddUsers/addUsers.sh
index 2905c24..7794205 100644
--- a/assignments/shell/AddUsers/addUsers.sh
+++ b/assignments/shell/AddUsers/addUsers.sh
@@ -1,9 +1,36 @@
-#
-#
-# useradd
-# chpasswd
-# chown
-# chmod
-# edquota
-#
+#!/bin/bash
+#  遍历文件目录下所有的文件，并打印打印普通文件，才有深度优先搜索方法
+#  递归调用函数
+filesearch()
+{
+    
+    filename2=(`ls`)	
+    for b  in ${filename2[*]}
+    do 	
+        if [ -d $b ]
+        then
+           cd $b	
+             filesearch $b
+           cd .. 
+        else
+           echo  "$b"	  
+        fi
+    done
+}
+firstsearch(){
+    filename1=(`ls`)	
+    for a  in ${filename1[*]}
+    do 
+      if [ -d $a ]
+      then 
+        
+         cd $a
+            filesearch $a 
+         cd ..         
+      else 
+         echo  "$a"
+      fi 
+   done
+}
 
+firstsearch
diff --git a/assignments/shell/AddUsers/addUsers.sh~ b/assignments/shell/AddUsers/addUsers.sh~
new file mode 100644
index 0000000..7794205
--- /dev/null
+++ b/assignments/shell/AddUsers/addUsers.sh~
@@ -0,0 +1,36 @@
+#!/bin/bash
+#  遍历文件目录下所有的文件，并打印打印普通文件，才有深度优先搜索方法
+#  递归调用函数
+filesearch()
+{
+    
+    filename2=(`ls`)	
+    for b  in ${filename2[*]}
+    do 	
+        if [ -d $b ]
+        then
+           cd $b	
+             filesearch $b
+           cd .. 
+        else
+           echo  "$b"	  
+        fi
+    done
+}
+firstsearch(){
+    filename1=(`ls`)	
+    for a  in ${filename1[*]}
+    do 
+      if [ -d $a ]
+      then 
+        
+         cd $a
+            filesearch $a 
+         cd ..         
+      else 
+         echo  "$a"
+      fi 
+   done
+}
+
+firstsearch

From 8eab3070f618a0a042a8814b364ffd1d2b5539c5 Mon Sep 17 00:00:00 2001
From: JornShen <shencanhui@foxmail.com>
Date: Mon, 18 Apr 2016 19:42:28 +0800
Subject: [PATCH 2/6] Delete addUsers.sh~

---
 assignments/shell/AddUsers/addUsers.sh~ | 36 -------------------------
 1 file changed, 36 deletions(-)
 delete mode 100644 assignments/shell/AddUsers/addUsers.sh~

diff --git a/assignments/shell/AddUsers/addUsers.sh~ b/assignments/shell/AddUsers/addUsers.sh~
deleted file mode 100644
index 7794205..0000000
--- a/assignments/shell/AddUsers/addUsers.sh~
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/bin/bash
-#  遍历文件目录下所有的文件，并打印打印普通文件，才有深度优先搜索方法
-#  递归调用函数
-filesearch()
-{
-    
-    filename2=(`ls`)	
-    for b  in ${filename2[*]}
-    do 	
-        if [ -d $b ]
-        then
-           cd $b	
-             filesearch $b
-           cd .. 
-        else
-           echo  "$b"	  
-        fi
-    done
-}
-firstsearch(){
-    filename1=(`ls`)	
-    for a  in ${filename1[*]}
-    do 
-      if [ -d $a ]
-      then 
-        
-         cd $a
-            filesearch $a 
-         cd ..         
-      else 
-         echo  "$a"
-      fi 
-   done
-}
-
-firstsearch

From 47d733a186a59ac92c335409e99c4b59d2cb7adb Mon Sep 17 00:00:00 2001
From: shencanhui <shencanhui@foxmail.com>
Date: Mon, 2 May 2016 15:09:31 +0800
Subject: [PATCH 3/6] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E9=99=A4=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 assignments/shell/AddUsers/addUsers.sh~       | 36 -------------------
 experiments/gcc-2-multi-source/calculator.c   |  5 +++
 experiments/gcc-2-multi-source/calculator.c~  | 22 ++++++++++++
 .../gcc-2-multi-source/include/calculator.h~  |  6 ++++
 experiments/gcc-2-multi-source/main.c         |  2 ++
 experiments/gcc-2-multi-source/main.c~        | 14 ++++++++
 6 files changed, 49 insertions(+), 36 deletions(-)
 delete mode 100644 assignments/shell/AddUsers/addUsers.sh~
 create mode 100644 experiments/gcc-2-multi-source/calculator.c~
 create mode 100644 experiments/gcc-2-multi-source/include/calculator.h~
 create mode 100644 experiments/gcc-2-multi-source/main.c~

diff --git a/assignments/shell/AddUsers/addUsers.sh~ b/assignments/shell/AddUsers/addUsers.sh~
deleted file mode 100644
index 7794205..0000000
--- a/assignments/shell/AddUsers/addUsers.sh~
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/bin/bash
-#  遍历文件目录下所有的文件，并打印打印普通文件，才有深度优先搜索方法
-#  递归调用函数
-filesearch()
-{
-    
-    filename2=(`ls`)	
-    for b  in ${filename2[*]}
-    do 	
-        if [ -d $b ]
-        then
-           cd $b	
-             filesearch $b
-           cd .. 
-        else
-           echo  "$b"	  
-        fi
-    done
-}
-firstsearch(){
-    filename1=(`ls`)	
-    for a  in ${filename1[*]}
-    do 
-      if [ -d $a ]
-      then 
-        
-         cd $a
-            filesearch $a 
-         cd ..         
-      else 
-         echo  "$a"
-      fi 
-   done
-}
-
-firstsearch
diff --git a/experiments/gcc-2-multi-source/calculator.c b/experiments/gcc-2-multi-source/calculator.c
index 391fc7f..2cd78d5 100644
--- a/experiments/gcc-2-multi-source/calculator.c
+++ b/experiments/gcc-2-multi-source/calculator.c
@@ -13,5 +13,10 @@ int multiply(int x, int y) {
 }
 
 int divide(int x, int divisor) {
+	//除法考虑分母为0的情况
+	if(divisor==0){
+		printf("Error!divisor is negative！");
+		return 99999999;
+	}
 	return x / divisor;
 }
diff --git a/experiments/gcc-2-multi-source/calculator.c~ b/experiments/gcc-2-multi-source/calculator.c~
new file mode 100644
index 0000000..43d9354
--- /dev/null
+++ b/experiments/gcc-2-multi-source/calculator.c~
@@ -0,0 +1,22 @@
+#include "include/calculator.h"
+
+int sum(int x, int y) {
+	return x + y;
+}
+
+int subtract(int x, int y) {
+	return x - y;
+}
+
+int multiply(int x, int y) {
+	return x * y;
+}
+
+int divide(int x, int divisor) {
+	//除法考虑分母为0的情况
+	if(divisor==0){
+		printf("Error!divisor is negative！");
+		return 0;
+	}
+	return x / divisor;
+}
diff --git a/experiments/gcc-2-multi-source/include/calculator.h~ b/experiments/gcc-2-multi-source/include/calculator.h~
new file mode 100644
index 0000000..7daefe5
--- /dev/null
+++ b/experiments/gcc-2-multi-source/include/calculator.h~
@@ -0,0 +1,6 @@
+
+int sum(int x, int y);
+int subtract(int x, int y);
+int multiply(int x, int y);
+int divide(int x, int divisor);
+
diff --git a/experiments/gcc-2-multi-source/main.c b/experiments/gcc-2-multi-source/main.c
index bdbb5b9..8c7bf43 100644
--- a/experiments/gcc-2-multi-source/main.c
+++ b/experiments/gcc-2-multi-source/main.c
@@ -7,6 +7,8 @@ int main(void) {
 	y = 3;
 
 	printf("%d + %d = %d\n", x, y, sum(2, 3));
+	printf("%d + %d = %d\n", x, y, divide(2, 3));
+	printf("%d + %d = %d\n", x, y, divide(2, 0));	
 
 	return 0;
 }
diff --git a/experiments/gcc-2-multi-source/main.c~ b/experiments/gcc-2-multi-source/main.c~
new file mode 100644
index 0000000..8c7bf43
--- /dev/null
+++ b/experiments/gcc-2-multi-source/main.c~
@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+int main(void) {
+	int x, y;
+	
+	x = 2;
+	y = 3;
+
+	printf("%d + %d = %d\n", x, y, sum(2, 3));
+	printf("%d + %d = %d\n", x, y, divide(2, 3));
+	printf("%d + %d = %d\n", x, y, divide(2, 0));	
+
+	return 0;
+}

From 596b1958df693c2c7da7b30f48d68a2f0e56b125 Mon Sep 17 00:00:00 2001
From: shencanhui <shencanhui@foxmail.com>
Date: Mon, 2 May 2016 15:41:51 +0800
Subject: [PATCH 4/6] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E9=99=A4=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 experiments/gcc-3-real-project/calculator.c   |  14 ++++++++---
 experiments/gcc-3-real-project/calculator.c~  |  23 ++++++++++++++++++
 .../gcc-3-real-project/include/calculator.h   |   2 +-
 .../gcc-3-real-project/include/calculator.h~  |   9 +++++++
 experiments/gcc-3-real-project/main           | Bin 0 -> 8768 bytes
 experiments/gcc-3-real-project/main.c         |   3 +++
 experiments/gcc-3-real-project/main.c~        |  17 +++++++++++++
 7 files changed, 63 insertions(+), 5 deletions(-)
 create mode 100644 experiments/gcc-3-real-project/calculator.c~
 create mode 100644 experiments/gcc-3-real-project/include/calculator.h~
 create mode 100755 experiments/gcc-3-real-project/main
 create mode 100644 experiments/gcc-3-real-project/main.c~

diff --git a/experiments/gcc-3-real-project/calculator.c b/experiments/gcc-3-real-project/calculator.c
index 391fc7f..6106941 100644
--- a/experiments/gcc-3-real-project/calculator.c
+++ b/experiments/gcc-3-real-project/calculator.c
@@ -1,7 +1,7 @@
 #include "include/calculator.h"
-
+#include "stdio.h"
 int sum(int x, int y) {
-	return x + y;
+	return x + y;	
 }
 
 int subtract(int x, int y) {
@@ -12,6 +12,12 @@ int multiply(int x, int y) {
 	return x * y;
 }
 
-int divide(int x, int divisor) {
-	return x / divisor;
+double divide(double x, double divisor) {
+	if(divisor==0){
+	    printf("Error! the divisor is zero! please check.\n");
+	    return 99999999;
+	}else {
+	
+	    return x / divisor;
+	}
 }
diff --git a/experiments/gcc-3-real-project/calculator.c~ b/experiments/gcc-3-real-project/calculator.c~
new file mode 100644
index 0000000..c5c66db
--- /dev/null
+++ b/experiments/gcc-3-real-project/calculator.c~
@@ -0,0 +1,23 @@
+#include "include/calculator.h"
+#include "stdio.h"
+int sum(int x, int y) {
+	return x + y;
+}
+
+int subtract(int x, int y) {
+	return x - y;
+}
+
+int multiply(int x, int y) {
+	return x * y;
+}
+
+int divide(int x, int divisor) {
+	if(divisor==0){
+	    printf("Error! the divisor is zero! please check.\n");
+	    return 99999999;
+	}else {
+	
+	    return x / divisor;
+	}
+}
diff --git a/experiments/gcc-3-real-project/include/calculator.h b/experiments/gcc-3-real-project/include/calculator.h
index a5e00e3..547dbe4 100644
--- a/experiments/gcc-3-real-project/include/calculator.h
+++ b/experiments/gcc-3-real-project/include/calculator.h
@@ -4,6 +4,6 @@
 int sum(int x, int y);
 int subtract(int x, int y);
 int multiply(int x, int y);
-int divide(int x, int divisor);
+double divide(double x, double divisor);
 
 #endif //_CALC_H
diff --git a/experiments/gcc-3-real-project/include/calculator.h~ b/experiments/gcc-3-real-project/include/calculator.h~
new file mode 100644
index 0000000..547dbe4
--- /dev/null
+++ b/experiments/gcc-3-real-project/include/calculator.h~
@@ -0,0 +1,9 @@
+#ifndef _CALC_H
+#define _CALC_H
+
+int sum(int x, int y);
+int subtract(int x, int y);
+int multiply(int x, int y);
+double divide(double x, double divisor);
+
+#endif //_CALC_H
diff --git a/experiments/gcc-3-real-project/main b/experiments/gcc-3-real-project/main
new file mode 100755
index 0000000000000000000000000000000000000000..a2161111bee7d0f03967e603f3140c1280cf3c4e
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z_N&hN`CKwjodU7FEmdX4FGAt;ubf|01zqf@IQubw$K}uaye{R>?c^}*$MQc>AdLIZ
z`yfL(y6sgu*j><ph_H?dVi(wdhYM$a=B?0k-A>c5bNy_nlrB-$&EJmGf0_b=o>DLF
b11Jaa<NolxM&D<>`VD2k>k!N&x$FNoLx~6K

literal 0
HcmV?d00001

diff --git a/experiments/gcc-3-real-project/main.c b/experiments/gcc-3-real-project/main.c
index 6798996..2438d76 100644
--- a/experiments/gcc-3-real-project/main.c
+++ b/experiments/gcc-3-real-project/main.c
@@ -10,5 +10,8 @@ int main(void) {
 
 	printf("%d - %d = %d\n", x, y, subtract(2, 3));
 
+	printf("%d / %d = %.2f\n", x, y,divide(2, 3));
+	
+	printf("%d / %d = %.2f\n", x, y, divide(2, 0));
 	return 0;
 }
diff --git a/experiments/gcc-3-real-project/main.c~ b/experiments/gcc-3-real-project/main.c~
new file mode 100644
index 0000000..2438d76
--- /dev/null
+++ b/experiments/gcc-3-real-project/main.c~
@@ -0,0 +1,17 @@
+#include <stdio.h>
+
+#include "include/calculator.h"
+
+int main(void) {
+	int x, y;
+	
+	x = 2;
+	y = 3;
+
+	printf("%d - %d = %d\n", x, y, subtract(2, 3));
+
+	printf("%d / %d = %.2f\n", x, y,divide(2, 3));
+	
+	printf("%d / %d = %.2f\n", x, y, divide(2, 0));
+	return 0;
+}

From 595dbfab5366475948c4204f9dcc814abf4dc055 Mon Sep 17 00:00:00 2001
From: shencanhui <shencanhui@foxmail.com>
Date: Mon, 2 May 2016 16:08:00 +0800
Subject: [PATCH 5/6] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E4=BA=86=E9=99=A4?=
 =?UTF-8?q?=E6=B3=95?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 experiments/gcc-4-optimize/calculator.c          | 11 +++++++++--
 experiments/gcc-4-optimize/include/calculator.h  |  2 +-
 experiments/gcc-4-optimize/include/calculator.h~ |  9 +++++++++
 3 files changed, 19 insertions(+), 3 deletions(-)
 create mode 100644 experiments/gcc-4-optimize/include/calculator.h~

diff --git a/experiments/gcc-4-optimize/calculator.c b/experiments/gcc-4-optimize/calculator.c
index 391fc7f..c12d3d4 100644
--- a/experiments/gcc-4-optimize/calculator.c
+++ b/experiments/gcc-4-optimize/calculator.c
@@ -1,4 +1,5 @@
 #include "include/calculator.h"
+#include <stdio.h>
 
 int sum(int x, int y) {
 	return x + y;
@@ -12,6 +13,12 @@ int multiply(int x, int y) {
 	return x * y;
 }
 
-int divide(int x, int divisor) {
-	return x / divisor;
+double divide(double x, double divisor){
+	if(divisor==0){
+	    printf("Error!divisor is zero");
+	    return 999999999;	
+	}else{
+	    return x / divisor;
+	}
+	
 }
diff --git a/experiments/gcc-4-optimize/include/calculator.h b/experiments/gcc-4-optimize/include/calculator.h
index a5e00e3..547dbe4 100644
--- a/experiments/gcc-4-optimize/include/calculator.h
+++ b/experiments/gcc-4-optimize/include/calculator.h
@@ -4,6 +4,6 @@
 int sum(int x, int y);
 int subtract(int x, int y);
 int multiply(int x, int y);
-int divide(int x, int divisor);
+double divide(double x, double divisor);
 
 #endif //_CALC_H
diff --git a/experiments/gcc-4-optimize/include/calculator.h~ b/experiments/gcc-4-optimize/include/calculator.h~
new file mode 100644
index 0000000..547dbe4
--- /dev/null
+++ b/experiments/gcc-4-optimize/include/calculator.h~
@@ -0,0 +1,9 @@
+#ifndef _CALC_H
+#define _CALC_H
+
+int sum(int x, int y);
+int subtract(int x, int y);
+int multiply(int x, int y);
+double divide(double x, double divisor);
+
+#endif //_CALC_H

From 40b4dd3c90f69f6072e0ead8572897ec8a3836f2 Mon Sep 17 00:00:00 2001
From: shencanhui <shencanhui@foxmail.com>
Date: Mon, 2 May 2016 16:18:44 +0800
Subject: [PATCH 6/6] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E4=BA=86=E6=95=B0?=
 =?UTF-8?q?=E7=BB=84=E7=9A=84=E9=94=99=E8=AF=AF?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 experiments/gcc-5-gdb/array.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/experiments/gcc-5-gdb/array.c b/experiments/gcc-5-gdb/array.c
index f12c568..e92db61 100644
--- a/experiments/gcc-5-gdb/array.c
+++ b/experiments/gcc-5-gdb/array.c
@@ -4,14 +4,14 @@
 
 void array_fill_with(int *array, int length, int fillWith) {
 	int i;
-	for (i = 0; i <= length; i++) {
+	for (i = 0; i < length; i++) {
 		array[i] = fillWith;
 	}
 }
 
 void array_add(int *arrayX, int *arrayY, int *arrayZ, int length) {
 	int i;
-	for (i = 0; i <= length; i++) {
+	for (i = 0; i < length; i++) {
 		arrayZ[i] = arrayX[i] + arrayY[i];
 	}
 }