def checkfermat ( a , b , c , n ) :

try :

a = int ( a )

except ValueError :

print "a is not a proper integer"

try :

b = int ( b )

except ValueError :

print "b is not a proper integer"

try :

c = int ( c )

except ValueError :

print "c is not a proper integer"

try :

n = int ( n )

except ValueError :

print "n is not a proper integer"

print "a**n + b**n = " , a**n + b**n , "c**n is:" , c**n

if a**n + b**n == c**n:

print "This case proves fermat's theorem wrong!"

else :

print "The theory holds."

supplyargs ( a , b , c , n )

def supplyargs ( a = '4' , b = '5' , c = '6' , n = '3' ) :

'supply args for checking fermats theorem'

print "values are a:" , a , "b:" , b , "c:" , c , "n:" , n

string = raw_input ( "type a,b,c, or n followed by a dash and the number, or type 'ready':" )

t = string [ 0 ]

if string == "ready" :

checkfermat ( a , b , c , n )

if t != "a" and t != "b" and t != "c" and t != "n" and string != "ready" :

print "Error: the first character was neither a,b,c or n."

supplyargs ( a , b , c , n )

if string != "ready" :

try :

t = string [ 1 ]

except IndexError :

print "The string is not long enough."

supplyargs ( a , b , c , n )

if t != "-" :

print "Error: the second character was not a dash(-)."

supplyargs ( a , b , c , n )

else :

print "running else"

t1 = string [ 0 ]

t2 = string [ 2 : ]

if t1 == 'a' :

a = t2

if t1 == 'b' :

b = t2

if t1 == 'c' :

c = t2

if t1 == 'n' :

n = t2

supplyargs ( a , b , c , n )