not sure how to add the english alphabet frequency to this code. and then I also dont know how to use that key to produce the plain text without doing 26 different if statements. c++ code answer please

Letter	Frequency
E	21912		E	12.02
T	16587		T	9.10
A	14810		A	8.12
O	14003		O	7.68
I	13318		I	7.31
N	12666		N	6.95
S	11450		S	6.28
R	10977		R	6.02
H	10795		H	5.92
D	7874		D	4.32
L	7253		L	3.98
U	5246		U	2.88
C	4943		C	2.71
M	4761		M	2.61
F	4200		F	2.30
Y	3853		Y	2.11
W	3819		W	2.09
G	3693		G	2.03
P	3316		P	1.82
B	2715		B	1.49
V	2019		V	1.11
K	1257		K	0.69
X	315		X	0.17
Q	205		Q	0.11
J	188		J	0.10
Z	128		Z	0.07

frequency percantages are on the right, use those and compare them with the frequencys of the cipher text. I have the frequencys of the ciper text, how do i compare the two and output a decrypted message?

Ive been asked to add more to my question.. I dont know how chegg chooses who to appoint to questions, but they obviously need to look into who they choose. READ THE QUESTION IN THE PICTURE, write a c++ code, i dont understand how you are not capable of understanding what the question is

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