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| author | Fuwn <[email protected]> | 2024-04-07 23:18:32 -0700 |
|---|---|---|
| committer | Fuwn <[email protected]> | 2024-04-07 23:18:32 -0700 |
| commit | c1b6ffe70bd281c6c230fd63fabcaac2aff47514 (patch) | |
| tree | e8af3b1782a7cd0754590ed618fddc1bdb9b7385 /chapter13/select.cxx | |
| download | dscode-main.tar.xz dscode-main.zip | |
Diffstat (limited to 'chapter13/select.cxx')
| -rw-r--r-- | chapter13/select.cxx | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/chapter13/select.cxx b/chapter13/select.cxx new file mode 100644 index 0000000..44514e9 --- /dev/null +++ b/chapter13/select.cxx @@ -0,0 +1,71 @@ +// FILE: select.cxx
+// An interactive test program for the selectionsort function
+
+#include <algorithm> // Provides swap
+#include <cstdlib> // Provides EXIT_SUCCESS, size_t
+#include <iostream> // Provides cout and cin
+using namespace std;
+
+// PROTOTYPE of the function used in this test program:
+void selectionsort(int data[ ], size_t n);
+// Precondition: data is an array with at least n components.
+// Postcondition: The elements are rearranged so that
+// data[0] <= data[1] <= ... <= data[n-1].
+
+int main( )
+{
+ const char BLANK = ' ';
+ const size_t ARRAY_SIZE = 10; // Number of elements in the array to be sorted
+ int data[ARRAY_SIZE]; // Array of integers to be sorted
+ int user_input; // Number typed by the user
+ size_t number_of_elements; // How much of the array is used
+ size_t i; // Array index
+
+ // Provide some instructions.
+ cout << "Please type up to " << ARRAY_SIZE << " positive integers. ";
+ cout << "Indicate the list's end with a zero." << endl;
+
+ // Read the input numbers.
+ number_of_elements = 0;
+ cin >> user_input;
+ while ((user_input != 0) && (number_of_elements < ARRAY_SIZE))
+ {
+ data[number_of_elements] = user_input;
+ number_of_elements++;
+ cin >> user_input;
+ }
+
+ // Sort the numbers, and print the result with two blanks after each number.
+ selectionsort(data, number_of_elements);
+ cout << "In sorted order, your numbers are: "<< endl;
+ for (i = 0; i < number_of_elements; i++)
+ cout << data[i] << BLANK << BLANK;
+ cout << endl;
+
+ return EXIT_SUCCESS;
+}
+
+void selectionsort(int data[ ], size_t n)
+// Library facilities used: algorithm, cstdlib
+{
+ size_t i, j, index_of_largest;
+ int largest;
+
+ if (n == 0)
+ return; // No work for an empty array.
+
+ for (i = n-1; i > 0; --i)
+ {
+ largest = data[0];
+ index_of_largest = 0;
+ for (j = 1; j <= i; ++j)
+ {
+ if (data[j] > largest)
+ {
+ largest = data[j];
+ index_of_largest = j;
+ }
+ }
+ swap(data[i], data[index_of_largest]);
+ }
+}
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