Replace e with E

Write a script to replace the character ‘e’ with ‘E’ in the string ‘Weekly Challenge’. Also print the number of times the character ‘e’ is found in the string.

#!/usr/bin/env tclsh

set times [regsub -all "e" "Weekly Challenge" "E" result]
puts "Find e $times times"
puts "Output: $result"

使用 Regular Expressions 來做替代字串的任務。

也可以使用 string map 來替代字串，下面是 Replace e with E 的其它寫法：

#!/usr/bin/env tclsh

set str "Weekly Challenge"
set count 0

foreach x [split $str {}] {
    if {$x == "e"} {
        incr count
    }
}
puts "Find e $count times"
set result [string map {e E} $str]
puts "Output: $result"

也可以在計算 e 數目的時候就同時建構字串：

#!/usr/bin/env tclsh

set str "Weekly Challenge"
set count 0
set result {}

foreach x [split $str {}] {
    if {$x == "e"} {
        incr count
        append result "E"
    } else {
        append result $x
    }
}
puts "Find e $count times"
puts "Output: $result"