Write a C program which inputs a sentence from the user and then inputs a character from the user. Then it counts and prints the number of occurrences of the character in the sentence.

Write a program that reads $3$ strings then concatenates them together in a one string.

Example:

char $str1[]=$abc;

char str $2[]={123}^{\text{'}\text{'}}$;

char str $3[]=$"abcdef";

char str $4[80]$;

str $4$ must contains:" abc $123$ abcdef