Add cheatsheet

1 files changed, 75 insertions, 0 deletions

diff --git a/tips/cheatsheet.cpp b/tips/cheatsheet.cpp
new file mode 100644
index 0000000..5901c6c
--- /dev/null
+++ b/tips/cheatsheet.cpp
@@ -0,0 +1,75 @@
+/* Cheatsheet.  Useful basic code to have around for this course. */
+
+// -----------------------------------------------------------------------------
+
+#ifndef FUN_HPP /* fun.hpp */
+#define FUN_HPP
+
+#define MAX     1000
+#define MAXLEN  100
+
+void qsort(int * v, int left, int right);
+void swap(int * v, int left, int right);
+
+#endif /* FUN_HPP */
+
+// -----------------------------------------------------------------------------
+
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+/* qsort: sort v[left]...v[right] into increasing order 
+
+   Quicksort.
+   Ref.:
+   * The C Programming Language (ANSI C) - pg. 87)
+   * https://en.wikipedia.org/wiki/Quicksort
+*/
+void qsort(int * v, int left, int right) {
+    int i, last;
+
+    /* do nothing if array has less than 2 elements */
+    if (left >= right)
+        return;
+
+    swap(v, left, (left + right) / 2); 
+    last = left;
+
+    /* partition */
+    for (i = left + 1; i <= right; i++) {
+        if (v[i] < v[left]) {
+            swap(v, ++last, i);
+        }
+    }
+
+    swap(v, left, last);        /* reset partition element */
+    qsort(v, left, last - 1);
+    qsort(v, last + 1, right);
+}
+
+void swap(int * v, int left, int right) {
+    int t = v[left];
+    v[left] = v[right];
+    v[right] = t;
+}
+
+
+/* insertion sort (optional) */
+
+/* memoria dinamica, metodo exacto */
+
+/* memoria dinamica, metodo por incrementos */
+/* UNTESTED*/
+void lectura_pedidos_metodo_incrementos(void * pedidos) {
+    // open file stream
+
+    // read in "buffers" (stack memory)
+
+    // write to heap memory
+}
+
+int main() {
+    return 0;
+}
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