Find the next iteration in loop python

Just go through the indices and process every pair of characters:

for i in range(len(some_string) - 1):
    if some_string[i] in target_list and some_string[i+1] in target_list:
        print ("correct")
        break

if i == len(some_string) - 1:
    print ("incorrect")

You can alternatively create a mapping and look for adjacent true positives:

m = [(char in target_list) for char in some_string]

for i in range(len(m) - 1):
    if m[i] and m[i+1]:
        print ("correct")
        break
if i == len(m) - 1:
    print ("incorrect")

Just use map:

    target_list=['t','a','r','g','e']

def toDict(list):
    mp  = {}
    for c in list:
        mp[c] = True
    return mp

d = toDict(target_list)

print("dict:" , d)    

def check(string, mp):
    count = 0
    for c in string:
        if(mp.get(c,False)):
            count = count+1
            if(count > 1):
                return True
        else:
            count = 0   
    return False


print("check:" , check("heytr", d))       
print("check:" , check("hyt", d))    
print("check:" , check("heyt", d)) 

from itertools import tee

def rolling_window(iterable, n=2):
    iterators = tee(iterable, n)
    for i, iterator in enumerate(iterators):
        for skip in range(i):
            next(iterator, None)
    return zip(*iterators)

def match(some_string, target, n=2):
    target = set(target)
    return any(target.issuperset(s) for s in rolling_window(some_string, n=n))

A regular expression solution.

import re

target_chars='target'

p = re.compile('[%s]{2}' % re.escape(target_chars))
m = p.search(some_string)
if m:
    print('correct')
else:
    print('incorrect')

You can also use any() and zip() for this:

target_list=["t","a","r","g","e","t"]

target_list = set(target_list)

some_strings = ["heytr", "hyt", "heyt"]

def match_strings(string, target_list):
    return any(x in target_list and y in target_list for x, y in zip(string, string[1:]))

for some_string in some_strings:
    if match_strings(some_string, target_list):
        print("correct")
    else:
        print("incorrect")

Which Outputs:

correct
incorrect
incorrect

Logic of above code:

• Converts target_list to a set, since set lookup is constant time. If you keep it as a list, then lookup time is linear.
• Uses zip() to create pairs of the current element and the next element, and checks if both of these elements exist in target_list. Then checks if any() of the pairs exist, which returns True if any of the pairs exist, and False if none exist.
• Then loop over all the strings in some_strings, and check the above for each one.

def judge(some_string):
for index in range(0,len(some_string)-1):
    if some_string[index] in target_list and some_string[index+1] in target_list:
        print("correct")
        break
else:
    print("incorrect")

judge("heytr") --correct
judge("hyt") -- incorrect
judge("heyt") --incorrect

For loop iterates on all character of the string checks if i and i+1 is present in target.if yes prints out correct. after all iterations of loop is over if no two character are found in target it comes to the else part of for loop and prints out incorrect.