ruby 笔记之一

1.

#input a lot of di
puts 3/5

puts 5/3.1

=begin
#注释

nihao


=end

2.

puts 3/5;puts 3/5.0

puts "程序演示" /
"连接";

3.

#关键字，运算符,分隔符,组成了这门语言
print("===测试右边的值是否在左边的范围之内/n") ;
puts (0..9)===3.15 ;

a = 1 ; b = 1.0 ;
print("测试==比较的内容/n") ;
puts a == b ;

print("测试eql比较的类型和值/n") ;

puts a.eql?(b) ;

print("测试equal是比较地址/n") ;

puts a.equal?(b) ;
4.

# if then else end
a = 4 ; b = 4 ;
if a == b then

print("相等/n") ;
else
print("不相等") ;
end

if a == 2 then
print("a is value 2") ;

elsif a == 3 then
print("a is value 3") ;
else
print("a is value 4/n") ;

end

5.

#case when else end
a = 3 ;

case a
when 1
print("a is value 1/n") ;

when 2
print("a is value 2/n") ;
else
print("a is value 3") ;
end

6.

# when end

a = 1 ;

while a<= 4
=begin
is while in if print add ()
is print warning:
warning is don't put space before argument
parenthese.
=end

print "a=",a ;
print "/n";
a+=1 ;

end

7.

# please calc 1..10 sum

a = 1 ;
sum = 0 ;
while a <= 10
sum += a ;
a += 1 ;
end
print "1..10=",sum,"/n";

#把1..10之间的素质打印出来
print 5<3/2,"/n" ;
if not 5<3/2 then
print("nihao/n") ;
end
a = 2 ;
while a <= 100
c = 1 ;
#只能被1和本身整除的数是素数
b = 2 ;
while b <= a/2
if a%b == 0 then
c = 2 ;
end
b += 1 ;
end

if c == 1 then
print a," " ;
end
a += 1 ;
end