Write a function that counts the occurrence of each letter in the string using the following header: void count(const string& s) Write a test program that reads a string, invokes the count function, and displays the non-zero counts. Here is a sample run: Enter a string: Welcome to New York! Enter c: 1 times e: 3 times k: 1 times 1: 1 times m: 1 times n: 1 times o: 3 times r: 1 times t: 1 times w: 2 times y: 1 times