s = input()
d = {}
for i in s:
try:
d[i] += 1
except:
d[i] = 1
a = 0
b = 0
for cnt in d.values():
if cnt % 2:
b += 1
else:
a += 1
if a == 0:
print(1)
elif b == 0:
print(0)
else:
print("0/1")