Документация

Previous | Table of Contents | Next |

## Exercise: Interest CalculatorFor this exercise, you're going to perform a compound interest calculation. This program will calculate the interest on a savings account, given some information about interest rates, deposits, and time. The formula you're going to use is as follows: Using your text editor, type the program from Listing 2.2 and save it as When you're done, try running the program by typing the following at a command line: perl Interest Listing 2.3 shows a sample of the Interest program's output. ## Listing 2.2. The Complete Source of the Interest Program1: #!/usr/bin/perl -w 2: 3: print "Monthly deposit amount? "; 4: $pmt=<STDIN>; 5: chomp $pmt; 6: 7: print "Annual Interest rate? (ex. 7% is .07) "; 8: $interest=<STDIN>; 9: chomp $interest; 10: 11: print "Number of months to deposit? "; 12: $mons=<STDIN>; 13: chomp $mons; 14: 15: # Formula requires a monthly interest 16: $interest/=12; 17: 18: $total=$pmt * ( ( ( 1 + $interest) ** $mons ) -1 )/ $interest; 19: 20: print "After $mons months, at $interest monthly you\n"; 21: print "will have $total.\n";
## Listing 2.3. Output from the Interest Program1: Monthly deposit amount? 180 2: Annual Interest rate? (ex. 6% is .06) .06 3: Number of months to deposit? 120 4: After 120 months, at 0.005 monthly you 5: will have 29498.2824251624. |

Previous | Table of Contents | Next |