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Problem Statement

Suppose you have a string \$S\$ which has length \$N\$ and is indexed from \0ドル\$ to \$N−1\$. String \$R\$ is the reverse of the string \$S\$. The string \$S\$ is funny if the condition \$|S_i−S_{i−1}|=|R_−R_{i−1}|\$ is true for every \$i\$ from \1ドル\$ to \$N−1\$.

(Note: Given a string \$str\$, \$str_i\$ denotes the ascii value of the \$i\$th character (0-indexed) of \$str\$. \$|x|\$ denotes the absolute value of an integer \$x\$)

Example

is_funny("acxz") returns True

is_funny("bcxz") returns False

Solution

def is_palindrome(ary):
 return ary == ary[::-1]
def create_difference_list(s):
 res = []
 for i in range(1, len(s)):
 res.append(abs(ord(s[i]) - ord(s[i-1])))
 return res
def is_happystr(s):
 return is_palindrome(create_difference_list(s))

Notes

• Have used slow version of palindrome check assuming string is not going to be too long. Hope it doesn't affect performance that much.
• Approached problem via functional style, could have done all the computation in the same loop but is it a good practice?

Problem Statement

Suppose you have a string \$S\$ which has length \$N\$ and is indexed from \0ドル\$ to \$N−1\$. String \$R\$ is the reverse of the string \$S\$. The string \$S\$ is funny if the condition \$|S_i−S_{i−1}|=|R_i−R_{i−1}|\$ is true for every \$i\$ from \1ドル\$ to \$N−1\$.

(Note: Given a string \$str\$, \$str_i\$ denotes the ascii value of the \$i\$th character (0-indexed) of \$str\$. \$|x|\$ denotes the absolute value of an integer \$x\$)

Example

is_funny("acxz") returns True

is_funny("bcxz") returns False

Solution

def is_palindrome(ary):
 return ary == ary[::-1]
def create_difference_list(s):
 res = []
 for i in range(1, len(s)):
 res.append(abs(ord(s[i]) - ord(s[i-1])))
 return res
def is_happystr(s):
 return is_palindrome(create_difference_list(s))

Notes

• Have used slow version of palindrome check assuming string is not going to be too long. Hope it doesn't affect performance that much.
• Approached problem via functional style, could have done all the computation in the same loop but is it a good practice?

Problem Statement

Suppose you have a string S which has length N and is indexed from 0 to N−1. String R is the reverse of the string S. The string S is funny if the condition |S_i−S_i−1|=|R_i−R_i−1| is true for every i from 1 to N−1.

(Note: Given a string str, str_i denotes the ascii value of the ith character (0-indexed) of str. |x| denotes the absolute value of an integer x)

Example

is_funny("acxz") returns True

is_funny("bcxz") returns False

Solution

def is_palindrome(ary):
 return ary == ary[::-1]
def create_difference_list(s):
 res = []
 for i in range(1, len(s)):
 res.append(abs(ord(s[i]) - ord(s[i-1])))
 return res
def is_happystr(s):
 return is_palindrome(create_difference_list(s))

Notes

• Have used slow version of palindrome check assuming string is not going to be too long. Hope it doesn't affect performance that much.
• Approached problem via functional style, could have done all the computation in the same loop but is it a good practice?

Problem Statement

Suppose you have a string \$S\$ which has length \$N\$ and is indexed from \0ドル\$ to \$N−1\$. String \$R\$ is the reverse of the string \$S\$. The string \$S\$ is funny if the condition \$|S_i−S_{i−1}|=|R_−R_{i−1}|\$ is true for every \$i\$ from \1ドル\$ to \$N−1\$.

(Note: Given a string \$str\$, \$str_i\$ denotes the ascii value of the \$i\$th character (0-indexed) of \$str\$. \$|x|\$ denotes the absolute value of an integer \$x\$)

Example

is_funny("acxz") returns True

is_funny("bcxz") returns False

Solution

def is_palindrome(ary):
 return ary == ary[::-1]
def create_difference_list(s):
 res = []
 for i in range(1, len(s)):
 res.append(abs(ord(s[i]) - ord(s[i-1])))
 return res
def is_happystr(s):
 return is_palindrome(create_difference_list(s))

Notes

• Have used slow version of palindrome check assuming string is not going to be too long. Hope it doesn't affect performance that much.
• Approached problem via functional style, could have done all the computation in the same loop but is it a good practice?

Problem Statement

Suppose you have a string S which has length N and is indexed from 0 to N−1. String R is the reverse of the string S. The string S is funny if the condition |Si−Si−1|=|Ri−Ri−1| is true for every i from 1 to N−1.

(Note: Given a string str, stri denotes the ascii value of the ith character (0-indexed) of str. |x| denotes the absolute value of an integer x)

Example

is_funny("acxz") returns True

is_funny("bcxz") returns False

Solution

def is_palindrome(ary):
 return ary == ary[::-1]
def create_difference_list(s):
 res = []
 for i in range(1, len(s)):
 res.append(abs(ord(s[i]) - ord(s[i-1])))
 return res
def is_happystr(s):
 return is_palindrome(create_difference_list(s))

Notes

• Have used slow version of palindrome check assuming string is not going to be too long. Hope it doesn't affect performance that much.
• Approached problem via functional style, could have done all the computation in the same loop but is it a good practice?

Problem Statement

Suppose you have a string S which has length N and is indexed from 0 to N−1. String R is the reverse of the string S. The string S is funny if the condition |S_i−S_i−1|=|R_i−R_i−1| is true for every i from 1 to N−1.

(Note: Given a string str, str_i denotes the ascii value of the ith character (0-indexed) of str. |x| denotes the absolute value of an integer x)

Example

is_funny("acxz") returns True

is_funny("bcxz") returns False

Solution

def is_palindrome(ary):
 return ary == ary[::-1]
def create_difference_list(s):
 res = []
 for i in range(1, len(s)):
 res.append(abs(ord(s[i]) - ord(s[i-1])))
 return res
def is_happystr(s):
 return is_palindrome(create_difference_list(s))

Notes

• Have used slow version of palindrome check assuming string is not going to be too long. Hope it doesn't affect performance that much.
• Approached problem via functional style, could have done all the computation in the same loop but is it a good practice?