1. Dr. Rabnud joined a social circle. At first he had 5 friends. He noticed the number of his friends grew in the following ways. In the first week, 1 friend was missing, and the number of remaining friends doubled; in the second week, 2 friends were missing, and the number of remaining friends doubled. Generally speaking, N friends are missing in the N week, and the number of remaining friends doubles. Write a program that calculates and displays the number of friends Dr. Rabnud each week. The program runs until it exceeds the Dunbar’s number. Dunbar number is a rough estimate of the maximum value of a member of a person who has a stable relationship in the social circle. What is the approximate value?
2. Write a program that requires the user to enter two floating-point numbers and print the result of dividing the difference between the two numbers by the product of the two numbers. The program should cycle through each pair of values entered by the user before the user enters a non-number.
3. Write a program, read 8 integers into the array, and then print the 8 integers in reverse order.
4. Write a program to create two double-type arrays containing 8 elements, and use a loop to prompt the user to enter 8 values for the first array. The value of the second array element is set to the sum of the accumulated elements of the first array. For example, the value of the fourth element of the second array is the sum of the first 4 elements of the first array, and the value of the fifth element of the second array is the sum of the first 5 elements of the first array (it can be done with a nested loop, but the 5th element of the second array is the sum of the fourth element of the second array and the 5th element of the first array. The task can be completed with just one loop, and there is no need to use a nested loop). Finally, the contents of the two arrays are displayed using a loop, the first array is displayed in one row, the second array is displayed in the next row of the first array, and each element corresponds to each element of the first array.
5. Write a program, read a line of input, and then print out the input content in reverse order. You can store the input in an array of char type, assuming that each line does not exceed the characters? Recall that according to the %c conversion description, the scanf() function can only read one character from the input at a time, and when the user presses the Enter key, the scanf() function will generate a newline character (\n).
6. Write a program to print a table, and print an integer, the square of the number, and the cubic of the number for each row. Requires the user to enter the upper and lower limits of the form. Use a for loop.
7. Use nested loops to print letters in the following format: ABCDEFGHIJKLMNOPQRSTU If your system does not use code encoded in numerical order, please refer to the solution in Exercise 3.
8. Write a program that prompts the user to enter capital letters. Use nested loops to print letters in the following pyramid format: Printing such a graph depends on the letters entered by the user. For example, the above graph is a print result after the user enters E. Tip: Use the outer loop to process the rows, and use 3 inner loops for each row to process spaces, print letters in ascending order, and print letters in descending order. If the system does not use ASCII or other code encoded in numerical order, refer to the solution in Exercise 3.
9. ChuckieLucky won $1 million (after tax), and he deposited the bonus into an account with an annual interest rate of 8%. On the last day of the year, Chuckie takes out $100,000. Write a program to calculate how many years Chuckie will withdraw the money from the account?
10. Daphne invested $100 at 10% of the single interest (that is, the annual investment profit is equivalent to 10% of the original investment). Deirdre invested $100 with a compound interest of 5% (that is, the interest is 5% of the current balance, including the previous interest). Write a program that calculates how many years Deirdre's investment will exceed Daphne and shows the investments of the two at that time.
11. Modify exercises to use a function to return the result of the calculation.
12. Write a program that requires the user to enter an upper bound integer and a lower bound integer, calculate the sum of squares of all integers from the upper bound to the lower bound, and display the calculation results. The program then continues to prompt the user to enter the upper and lower bound integers and displays the result until the upper bound integer entered by the user is less than the lower bound integer. The program run example is as follows: Enterlower and upper inner limits:59Thesumsofthesquaresfrom25to81is255Enternextsetoflimits:325Thesumsofthesquaresfrom9to625is5520Enternextsetoflimits:55Done
13. Write a program to read a word into a character array, and then print the word in reverse order. Tip: The strlen() function (introduced in Chapter 4) can be used to calculate the subscript of the last character of the array.
14. Use nested loops to print letters in the following format: FFEFEDFEDCFEDCBFEDCBA Note: If your system does not use ASCII or other code encoded in numerical order, you can initialize the character array into letters in the alphabet: charlets[27] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; then use the array subscript to select individual letters, such as lets[0] is 'A', etc.
15. Consider the following two infinite sequences: 0+0/0+0/0+0/0+…0-0/0+0/0-0/0+… Write a program to calculate the sum of these two infinite sequences until they reach a certain number of times. Tip: Multiply odd numbers - 1s - even numbers - 1s - 1s? Let the user enter the specified number of times interactively, and end the input when the user enters 0 or negative values. Check the sum after running 100 items, 1000 items, and 10000 items. Do you find that each sequence converges to a certain value?
16. Write a program to create an int type array containing 8 elements, and set the array elements to the first 8 powers of 2 respectively. Use a for loop to set the value of an array element and use a dowhile loop to display the value of an array element.
17. Use nested loops to print characters in the following format: $$$$$$$$$$$$$$$