procedures

1 files changed, 46 insertions, 0 deletions

diff --git a/3/6_control/27_while_for.c b/3/6_control/27_while_for.c
new file mode 100644
index 0000000..f7f73f7
--- /dev/null
+++ b/3/6_control/27_while_for.c
@@ -0,0 +1,46 @@
+#include <stdio.h>
+
+long fact_for(long n) {
+    long i;
+    long result = 1;
+    for (i = 2; i <= n; i++) {
+        result *= i;
+    }
+    return result;
+}
+
+// guarded do
+//
+// init-s
+// t = test-e;
+// if (!t) goto done;
+//
+// loop:
+//   body-s
+//   update-e;
+//   t = test-e;
+//   if (t) goto loop;
+//
+// done:
+
+long fact_for_gd_goto(long n) {
+    long i = 2;
+    long result = 1;
+
+    int t = i<=n;
+    if (!t) {
+        goto done;
+    }
+loop:
+    result *= i;
+    i++;
+    t = i<=n;
+    if (t) goto loop;
+done:
+    return result;
+}
+
+int main() {
+    printf("for: %ld, goto: %ld\n", fact_for(5), fact_for_gd_goto(5));
+    return 0;
+}