##### Short Problem Definition:

Sid is obsessed with reading short stories. Being a CS student, he is doing some interesting frequency analysis with the books. He chooses strings S1 and S2 in such a way that | len(S1)−len(S2) | ≤1 |

##### Link

##### Complexity:

time complexity is `O(N)`

space complexity is `O(N)`

##### Execution:

Compare the frequency counts of the two parts.

##### Solution:

```
#!/usr/bin/py
def buildMap(s):
the_map = {}
for char in s:
if char not in the_map:
the_map[char] = 1
else:
the_map[char] +=1
return the_map
def anagram(s):
if len(s)%2 == 1:
return -1
mid = len(s)//2
s1 = s[:mid]
s2 = s[mid:]
map1 = buildMap(s1)
map2 = buildMap(s2)
diff_cnt = 0
for key in map2.keys():
if key not in map1:
diff_cnt += map2[key]
else:
diff_cnt += max(0, map2[key]-map1[key])
return diff_cnt
if __name__ == '__main__':
t = input()
for _ in xrange(t):
s = raw_input()
print anagram(s)
```