一个shell写的加法机，请高手帮忙修改一下

shell初学者，不要见笑。请高手帮忙修正一下：
已知问题：
1.不能屏蔽英文字符和符号的输入。
2.减法错误。

一共两个文件，addrobot和numf
addrobot内容：

1. #!/bin/sh
   
2. clear
   
3. cat /dev/null > num.txt
   
4. cat /dev/null > numf.txt
   
5. while [ TRUE ]
   
6. do
   
7. clear
   
8. line=`wc -l num.txt|awk '{ print $1 }'`
   
9. sum=`awk 'BEGIN { sum = 0 } { sum = sum + $1} END { OFMT = "%.2f"; print sum/100; }' num.txt`
   
10. tput cup 25 20
    
11. echo $line行                        总计：$sum
    
12. tput cup 1 8
    
13. echo  ★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
    
14. echo -----------------------------------------------------xlink-----------------
    
15. for x in 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
    
16. do
    
17. tput cup $x 4
    
18. echo 数据录入:
    
19. tput cup $x 14
    
20. read num
    
21. if [ $num = q 2>/dev/null ]
    
22. then
    
23. exit
    
24. elif [ -z $num ]
    
25. then
    
26. tput cup $x 14
    
27. echo "非法数值"
    
28. elif [ $num -eq 0 2>/dev/null ]
    
29. then
    
30. tput cup $x 14
    
31. echo "非法数值"
    
32. else
    
33. tput cup $x 40
    
34. echo $num>tmp
    
35. echo $num>>num.txt
    
36. No=`wc -l num.txt|awk '{print $1}'`
    
37. echo No.$No
    
38. line=`wc -l num.txt|awk '{ print $1 }'`
    
39. sum=`awk 'BEGIN { sum = 0 } { sum = sum + $1} END { OFMT = "%.2f"; print sum/100; }' num.txt`
    
40. tput cup 25 20
    
41. echo 共$line行                        总计：$sum
    
42. tput cup $x 48
    
43. ./numf
    
44. tput cup $x 14
    
45. fi
    
46. done
    
47. done

复制代码

numf内容：

1. #!/bin/sh
   
2. n=`awk '{print length($1)}' tmp`
   
3. if [ $n = 1 ]
   
4. then read num<tmp
   
5. echo 0.0$num
   
6. echo 0.0$num>>numf.txt
   
7. elif [ $n = 2 ]
   
8. then read num<tmp
   
9. echo 0.$num
   
10. echo 0.$num>>numf.txt
    
11. elif [ $n = 3 ]
    
12. then read num<tmp
    
13. na=`echo $num|cut -c1`
    
14. nb=`echo $num|cut -c2-3`
    
15. echo ${na}.${nb}
    
16. echo ${na}.${nb}>>numf.txt
    
17. elif [ $n = 4 ]
    
18. then read num<tmp
    
19. na=`echo $num|cut -c1-2`
    
20. nb=`echo $num|cut -c3-4`
    
21. echo ${na}.${nb}
    
22. echo ${na}.${nb}>>numf.txt
    
23. elif [ $n = 5 ]
    
24. then read num<tmp
    
25. na=`echo $num|cut -c1-3`
    
26. nb=`echo $num|cut -c4-5`
    
27. echo ${na}.${nb}
    
28. echo ${na}.${nb}>>numf.txt
    
29. elif [ $n = 6 ]
    
30. then read num<tmp
    
31. na=`echo $num|cut -c1`
    
32. nb=`echo $num|cut -c2-4`
    
33. nc=`echo $num|cut -c5-6`
    
34. echo ${na},${nb}.${nc}
    
35. echo ${na},${nb}.${nc}>>numf.txt
    
36. elif [ $n = 7 ]
    
37. then read num<tmp
    
38. na=`echo $num|cut -c1-2`
    
39. nb=`echo $num|cut -c3-5`
    
40. nc=`echo $num|cut -c6-7`
    
41. echo ${na},${nb}.${nc}
    
42. echo ${na},${nb}.${nc}>>numf.txt
    
43. elif [ $n = 8 ]
    
44. then read num<tmp
    
45. na=`echo $num|cut -c1-3`
    
46. nb=`echo $num|cut -c4-6`
    
47. nc=`echo $num|cut -c7-8`
    
48. echo ${na},${nb}.${nc}
    
49. echo ${na},${nb}.${nc}>>numf.txt
    
50. elif [ $n = 9 ]
    
51. then read num<tmp
    
52. na=`echo $num|cut -c1`
    
53. nb=`echo $num|cut -c2-4`
    
54. nc=`echo $num|cut -c5-7`
    
55. nd=`echo $num|cut -c8-9`
    
56. echo ${na},${nb},${nc}.${nd}
    
57. echo ${na},${nb},${nc}.${nd}>>numf.txt
    
58. elif [ $n = 10 ]
    
59. then read num<tmp
    
60. na=`echo $num|cut -c1-2`
    
61. nb=`echo $num|cut -c3-5`
    
62. nc=`echo $num|cut -c6-8`
    
63. nd=`echo $num|cut -c9-10`
    
64. echo ${na},${nb},${nc}.${nd}
    
65. echo ${na},${nb},${nc}.${nd}>>numf.txt
    
66. elif [ $n = 11 ]
    
67. then read num<tmp
    
68. na=`echo $num|cut -c1-3`
    
69. nb=`echo $num|cut -c4-6`
    
70. nc=`echo $num|cut -c7-9`
    
71. nd=`echo $num|cut -c10-11`
    
72. echo ${na},${nb},${nc}.${nd}
    
73. echo ${na},${nb},${nc}.${nd}>>numf.txt
    
74. elif [ $n = 12 ]
    
75. then read num<tmp
    
76. na=`echo $num|cut -c1`
    
77. nb=`echo $num|cut -c2-4`
    
78. nc=`echo $num|cut -c5-7`
    
79. nd=`echo $num|cut -c8-10`
    
80. ne=`echo $num|cut -c11-12`
    
81. echo ${na},${nb},${nc},${nd}.${ne}
    
82. echo ${na},${nb},${nc},${nd}.${ne}>>numf.txt
    
83. elif [ $n = 13 ]
    
84. then read num<tmp
    
85. na=`echo $num|cut -c1-2`
    
86. nb=`echo $num|cut -c3-5`
    
87. nc=`echo $num|cut -c6-8`
    
88. nd=`echo $num|cut -c9-11`
    
89. ne=`echo $num|cut -c12-13`
    
90. echo ${na},${nb},${nc},${nd}.${ne}
    
91. echo ${na},${nb},${nc},${nd}.${ne}>>numf.txt
    
92. elif [ $n = 14 ]
    
93. then read num<tmp
    
94. na=`echo $num|cut -c1-3`
    
95. nb=`echo $num|cut -c4-6`
    
96. nc=`echo $num|cut -c7-9`
    
97. nd=`echo $num|cut -c10-12`
    
98. ne=`echo $num|cut -c13-14`
    
99. echo ${na},${nb},${nc},${nd}.${ne}
    
100. echo ${na},${nb}.${nc},${nd}.${ne}>>numf.txt
     
101. else
     
102. :
     
103. fi

复制代码