I am beginner and decided to write a program for tic tac toe and I found that I m stuck in one error which I can't observe when I give input move as 1,2,3,4,5 and 6 program ends fine after getting a combo of 3 but when I include 7,8 and 9 In input move it programs does not end import random import time def k_kno(): a='[1] | [2] | [3]' b='[4] | [5] | [6]' c='[7] | [8] | [9]' d='_______________' k_opt= str(input('do you want to know input keys to play game(Y/N) :')) time.sleep(.5) if k_opt=='y' or k_opt=='Y': print('') print(a) print(d) print(b) print(d) print(c) time.sleep(1) print('') print('ok lets proceed towards game') else: time.sleep(.5) print('') print('ok lets proceed towards game') time.sleep(.5) alv_move=[1,2,3,4,5,6,7,8,9] def game(): a='[1] | [2] | [3]' b='[4] | [5] | [6]' c='[7] | [8] | [9]' d='_______________' while a[1]!=a[7]==a[13] or a[1]==a[7]!=a[13] or a[1]!=a[7]!=a[13] and b[1]!=b[7]!=b[13] or b[1]!=b[7]==b[13] or b[1]==b[7]!=b[13] and c[1]!=c[7]!=c[13] or c[1]!=c[7]==c[13] or c[1]==c[7]!=c[13] and a[1]!=b[7]!=c[13] or a[1]!=b[7]==c[13] or a[1]==b[7]!=c[13] and a[13]!=b[7]!=c[1] or a[13]==b[7]!=c[1] or a[13]!=b[7]==c[1] and a[1]!=b[1]!=c[1] or a[1]==b[1]!=c[1] or a[1]!=b[1]==c[1] and a[13]!=b[13]!=c[13] or a[13]==b[13]!=c[13] or a[13]!=b[13]==c[13] and a[7]!=b[7]!=c[7] or a[7]==b[7]!=c[7] or a[7]!=b[7]==c[7] : print('') pO=int(input('enter your move:')) if pO==1: a=a.replace('[1] ',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==2: a=a.replace('[2]',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==3: a=a.replace('[3]',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==4: b=b.replace('[4]',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==5: b=b.replace('[5]',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==6: b=b.replace('[6]',' O ') print(a) print(d) print(b) print(d) print(c) if pO==8: c=c.replace('[8] ',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==9: c=c.replace('[9]',' O ') print(a) print(d) print(b) print(d) print(c) elif pO==7: c=c.replace('[7]',' O ') print(a) print(d) print(b) print(d) print(c) else: print('invalid move, turn cut') print('game over') k_kno() game()