Python finding index of elements with certain conditions -

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• find longest repetitive sequence in string 5 answers

i have following string:

array = "tqtdtqd" 

for each d in array, there anyway know how many consecutive t's or d's before , after each d same letter right before each d. 1st d, letter right before t, want find how many consecutive t's before , after 1st d. 2nd d, letter right before q, want find # of consecutive q's before , after 2nd d.

for instance, 1st d, there 1 t before d , 1 t after showing until there q. (e.g: 1st d, "tdt")

for 2nd d, there 1 consecutive q before or no q after

i did start following python codes find positions of each t,q,d:

get_indexes = lambda x, xs: [i (y, i) in zip(xs, range(len(xs))) if x == y] t_position = get_indexes("t",array) q_position = get_indexes("q",array) d_position = get_indexes("d",array)  

and tried find out t's before each d.

for each in range(0,len(d_position)):   rightbefored = array[d_position[each]-1]   numberoft = []   eachofallbefore in reversed(range(0,d_position[each])):     if array[eachofallbefore] ==rightbefored:       numberoft.append(array[eachofallbefore])       print (numberoft) 

but results these 2 d's 1st d:["t","t"], 2nd d: ["q","q"], seems prints out t or q's before each d,

1. i wondering if add check point stop loop once consecutive t/q's end.
2. also wonder if use same method finding consecutive t/q's after each d.

many thx!

i think works:

import re def sequences(s):     xdx = re.findall(r"['q']+['d']['q']*|['t']+['d']['t']*", s)      i, d_group in enumerate(xdx):         before, after = d_group.split('d')         print("for d{0} there {1}({2})s before , {3}({2})s after".format(i+1, len(before), before[0], len(after)))   if __name__ == "__main__":      sequences('qqqdqqtqdqqtdtdqq')