test subdirectory

test/old/sort.c

@@ -0,0 +1,47 @@
+int printf(char* format, ...);
+int scanf(char* format, ...);
+int exit(int status);
+
+void assert_eq(int expected, int actual) {
+    if (expected != actual) {
+        printf("expected: %d, actual: %d\n", expected, actual);
+        exit(1);
+    }
+}
+
+void swap(int* a, int* b) {
+    int t = *a;
+    *a = *b;
+    *b = t;
+}
+
+void sort(int a[], int n) {
+    for (int i = 0; i < n; i++) {
+        for (int j = i + 1; j < n; j++) {
+            if (a[i] > a[j]) {
+                swap(&a[i], &a[j]);
+                assert_eq(i - j, &a[i] - &a[j]);
+                assert_eq(j - i, &a[j] - &a[i]);
+                assert_eq(a[i], *(a + i));
+                assert_eq(i[a], *(i + a));
+                assert_eq(a[j - i], *(a + (j - i)));
+                assert_eq(j[a - i], *(j + (a - i)));
+            }
+        }
+    }
+}
+
+int a[100];
+int n;
+
+int main() {
+    scanf("%d", &n);
+    for (int i = 0; i < n; i++) {
+        scanf("%d", &a[i]);
+    }
+    sort(a, n);
+    for (int i = 0; i < n; i++) {
+        printf("%d ", a[i]);
+    }
+    printf("\n");
+}