242. Valid Anagram

Description:

Given two strings s and t, return true if t is an anagram of s, and false otherwise.

'''
[1] sort)

idea::
1. sort both s and t
2. check s[i]==t[i]

code::
def isAnagram(self, s: str, t: str) -> bool:
    if len(s)!=len(t):
        return False

    s_list=sorted(s)
    t_list=sorted(t)

    for i in range(len(s_list)):
        if s_list[i]!=t_list[i]:
            return False
    return True

-T/C: O(nlogn + mlogm) # n==len(s), m==len(t)
-S/C: O(m+n)
'''

'''
[2] hashmap)

code::
def isAnagram(self, s: str, t: str) -> bool:
    if len(s)!=len(t):
        return False

    smap={}
    tmap={}

    for c in s:
        if c in smap:
            smap[c]+=1
        else:
            smap[c]=1

    for c in t:
        if c in tmap:
            tmap[c]+=1
        else:
            tmap[c]=1

    for c,val in smap.items():
        if not c in tmap or val!=tmap[c]:
            return False
    return True
    
-T/C: O(m+n)
-S/C: O(m+n)
'''

class Solution:
    def isAnagram(self, s: str, t: str) -> bool:
        if len(s)!=len(t):
            return False
        
        smap={}
        tmap={}
        
        for c in s:
            if c in smap:
                smap[c]+=1
            else:
                smap[c]=1
        
        for c in t:
            if c in tmap:
                tmap[c]+=1
            else:
                tmap[c]=1
        
        for c,val in smap.items():
            if not c in tmap or val!=tmap[c]:
                return False
        return True