foo.c:1:1: warning: data definition has no type or storage class
s = str(input())
^
foo.c:1:1: warning: type defaults to 'int' in declaration of 's' [-Wimplicit-int]
foo.c:1:5: warning: implicit declaration of function 'str' [-Wimplicit-function-declaration]
s = str(input())
^~~
foo.c:1:9: warning: implicit declaration of function 'input' [-Wimplicit-function-declaration]
s = str(input())
^~~~~
foo.c:1:5: error: initializer element is not constant
s = str(input())
^~~
foo.c:2:1: error: expected ',' or ';' before 'x'
x = len(s)
^