将十六进制格式的文本转换为C中的字符

I am trying to decrypt a cipher text in C. The cipher text appeared to be in form of symbols and unreadable characters and I was unable to read the cipher text stored in this from a file properly hence the decryption was failing. So I tried a different method where I stored the cipher text in form of hexadecimal by doing:I am trying to decrypt a cipher text in C. The