comefrom: <doocs>0028.Find the Index of the First Occurrence in a String_1.py
code: def strStr( haystack, needle):
      for i in range(len(haystack) - len(needle) + 1):
          p = i
          q = 0
          while p < len(haystack) and q < len(needle) and haystack[p] == needle[q]:
              p += 1
              q += 1
      
          if q == len(needle):
              return i
      
      return -1
masked: def sample_funcname ( var_0 , var_1 ) :
      for var_5 in range ( len ( var_0 ) - len ( var_1 ) + 1 ) :
          var_6 = var_5
          var_8 = 0
          while var_6 < len ( var_0 ) and var_8 < len ( var_1 ) and var_0 [ var_6 ] == var_1 [ var_8 ] :
              var_6 += 1
              var_8 += 1
          if var_8 == len ( var_1 ) :
              return var_5
      return - 1
  