The following pseudocode describes how to obtain the name of a day, given the day number (0 = Sunday, 1 = Monday, and so on.)

Declare a string called names containing "SunMonTueWedThuFriSat". Compute the starting position as 3 x the day number. Extract the substring of names at the starting position with length 3.

Check this pseudocode, using the day number 4. Draw a diagram of the string that is being computed, similar to Figure 5 (See BJLO: Chapter 2, Section 2.5.6 (Substrings)). Suppose you are given a string str and two positions i and j, where i comes before j. The following pseudocode describes how to swap two letters in a word.

We are given a string str and two positions i and j. (i comes before j) Set first to the substring from the start of the string to the last position before i. Set middle to the substring from positions i + 1 to j - 1. Set last to the substring from position j + 1 to the end of the string. Concatenate the following five strings: first, the string containing just the character at position j, middle, the string containing just the character at position i, and last.

Check this pseudocode, using the string "Gateway" and positions 2 and 4. Draw a diagram of the string that is being computed, similar to Figure 5 (See BJLO: Chapter 2, Section 2.5.6 (Substrings)).