/* missing precondition */

public String getChar(String str, int n) {

return str.substring(n, n 1); }

Write down the most appropriate precondition for the method so that it does not throw an exception.

Answer:

An appropriate precondition is:

0 <= n && n <= str.length() - 1

Explanation:

Required:

Write down an appropriate pre-condition for the program

From the question, we understand that the method accepts two parameters:

str -> A string value

n -> An integer value which represents the index of character to return from the string str

It should be noted that:

n must be within the range of 0 and str.length()-1

Take for instance:

str = "ABCDE";

n must be within the range 0 to 4 (inclusive) in order not to raise an exception. This is so because the string index starts at 0 and stops at 1 less than the length of the string.

Hence, the precondition can be written as:

0 <= n && n <= str.length() - 1

Which means: n = 0 to length - 1

Write a program that reads an integer between o and 1000 and adds all the digits in the integer. For example, if an integer is 932, the sum of all the digits is 14. Hint: Use the % operator to extract digits, and use the / operator to remove the extracted digit. For instance, 932 % 10=2 and 932/10 =93. Here is a sample run:
Enter a number between 0 and 1000 : 999
The sum of digits is 27.

Identify the correct characteristics of Python lists. Check all that apply. Python lists are enclosed in curly braces { }. Python lists contain items separated by commas. Python lists are versatile Python data types. Python lists may use single quotes, double quotes, or no quotes.

What email program would you suggest and why?

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