Python String functions for leetcode

  • print(f'best RF score: {grid.best_score_:.3f}')
  • str.index(sub[,start[,end]])
  • str.strip() remove spaces at the beginning and the end
    • strip(str-not-want)
  • lower()
    • print(str.upper())
    • print(str.lower())
    • print(str.capitalize()) # Only first letter big
    • print(str.title()) # This Is A Title
  • s.find(c), s.rfind(c)
    • "hello".find("l") -> 2
    • "hello".rfind("l") -> 3
  • s.split('')
    • a = ''.join(a.split())
      • remove blank
  • replace(old, new[, max])
  • ''.join(str(e) for e in list)
    • list to str
  • s.isdigit(), s.isalpha
    • s.isalnum() # is num or alpha
    • if i.lstrip(’-‘).isdigit(): check number<0
  • ord , chr
    • ord('A') get 65
    • chr(65) get A
    • a = (chr(ord('0') + x % 10)) x:123 get: str type ‘3’
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