Warning(s):

source.kt:8:15: warning: conditional branch result of type Char is implicitly cast to Any
			    x<=34->'W'
              ^
source.kt:9:24: warning: conditional branch result of type Char is implicitly cast to Any
			    x>=35 && x<=54->'S'
                       ^
source.kt:10:24: warning: conditional branch result of type Char is implicitly cast to Any
			    x>=55 && x<=64->'C'
                       ^
source.kt:11:24: warning: conditional branch result of type Char is implicitly cast to Any
			    x>=65 && x<=74->'B'
                       ^
source.kt:12:25: warning: conditional branch result of type Char is implicitly cast to Any
			    x>=75 && x<=100->'A'
                        ^
source.kt:13:14: warning: conditional branch result of type String is implicitly cast to Any
			    else->"error" }
             ^
source.kt:20:16: warning: conditional branch result of type Char is implicitly cast to Any
			    xx<=34->'W'
               ^
source.kt:21:26: warning: conditional branch result of type Char is implicitly cast to Any
			    xx>=35 && xx<=54->'S'
                         ^
source.kt:22:26: warning: conditional branch result of type Char is implicitly cast to Any
			    xx>=55 && xx<=64->'C'
                         ^
source.kt:23:26: warning: conditional branch result of type Char is implicitly cast to Any
			    xx>=65 && xx<=74->'B'
                         ^
source.kt:24:27: warning: conditional branch result of type Char is implicitly cast to Any
			    xx>=75 && xx<=100->'A'
                          ^
source.kt:25:14: warning: conditional branch result of type String is implicitly cast to Any
			    else->"error" }
             ^
source.kt:32:17: warning: conditional branch result of type Char is implicitly cast to Any
			    xxx<=34->'W'
                ^
source.kt:33:28: warning: conditional branch result of type Char is implicitly cast to Any
			    xxx>=35 && xxx<=54->'S'
                           ^
source.kt:34:28: warning: conditional branch result of type Char is implicitly cast to Any
			    xxx>=55 && xxx<=64->'C'
                           ^
source.kt:35:28: warning: conditional branch result of type Char is implicitly cast to Any
			    xxx>=65 && xxx<=74->'B'
                           ^
source.kt:36:29: warning: conditional branch result of type Char is implicitly cast to Any
			    xxx>=75 && xxx<=100->'A'
                            ^
source.kt:37:14: warning: conditional branch result of type String is implicitly cast to Any
			    else->"error" }
             ^