Add multilingual language and systems learning tracks

en/objectivec-practice-20261101/lesson-2/main.m

@@ -0,0 +1,17 @@
+#import <Foundation/Foundation.h>
+#include <stdio.h>
+#include <assert.h>
+@interface StudyPlan : NSObject
+- (int)completed;
+@end
+@implementation StudyPlan
+- (int)completed { return 3; }
+@end
+int main(void) {
+    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
+    StudyPlan *plan = [[StudyPlan alloc] init];
+    printf("%d\n", [plan completed]);
+    [plan release];
+    [pool drain];
+    return 0;
+}