Java vs. C/CPP for competitive programming



If you’re here, chances are, you’ve decided to enter the world of competitive programming. And now, like every other fresher, you’re confused about the language to pick, right?

Java vs. C/CPP has been an ongoing debate since the advent of the competitive program. None of these languages trump the others, and it’s all about your preferences and needs. However, if you’re an absolute beginner, these key points will help you make a more informed decision:

  1. C/CPP:
  • C++ does not force object-oriented programming:  Unlike Java, the C++ language doesn’t force object-oriented programming, it merely supports. It. CPP provides useful extensions that can facilitate object-oriented programming thus allowing you to enjoy the best of both worlds.
  • Parameterized types: The “template” keyword in C++ allows the coder to write generic implementations of algorithms which can come in quite handy in the long run. In C, one could write a generic list implementation with an element like:

struct element_t
      struct element_t *next, *prev;
      void *element;

C++ allows you to write something like:

template <typename T>
struct element_t
   element_t<T> *next, *prev;
   T element;

  • A vast standard library:  C++, being a successor of the mighty C, allows the full use of the standard C libraries as well as the advanced libraries of C++. The most useful library is the Standard Template Library (STL). The STL contains some valuable templates like searching and sorting routines and implementation of most-used algorithms. It also includes useful data structures like maps, sets, lists, trees, graphs, etc. All of the STL routines and data structures are tailored to specific programmer needs – all the programmer has to do is fill in the types.

For example, to implement Binary Search, Java requires us to write a custom function. Whereas, in C++ Binary Search STL  routine is defined as

binary_search(startaddress, endaddress, valuetofind)

The above routine can be used without spending a lot of time on the logic behind something as trivial as binary search, thereby saving the coder’s time.

  1. Java:
  • STL vs. containers: C++ provides well designed STLs, whereas Java has Containers. The benefit of containers over STLs is that there are a few situations where STL doesn’t have a direct solution. For example, in case of priority_queue in STL, it doesn’t support decrease-key operation which is required for implementations of essential algorithms like Prim’s and Dijkstra’s.
  • Exception Handling in Java is incomparable: Java is known and appreciated for being exceptional in exception handling. It trumps C/C++ in this aspect. For example, it’s a lot easier to trace an ArrayIndexOutOfBound segmentation fault in Java.
  • Time Limit Exceeds: This is where Java comes second to C++. If you’re using Java, you might come across a TLE error due to Java being slightly slower.
  • Big integer and Regular Expressions: One of the biggest advantages of Java over C++ is the availability of libraries like Biginteger, Regular Expressions, and geometry library. These libraries make day-to-day competitive programming challenges easier to tackle.

C++ vs Java

  • Java requires more lines of code: Writing codes in Java uses a lot of syntaxes. This makes Java a great tool by providing the developers with granular control over their code. But, competitive programming demands speed, so, it’s recommended to pick Java only if you have some prior knowledge of coding in Java.    
  • STL vs. Containers: As we discussed above, STLs are tailor-made for competitive programmers, but some programmers still prefer containers.
  • C++ is more Popular: Be it the origin year or the comfort of use, but C++ outstands Java regarding the number of users that use the language.
  • C++ saves time: Java is no doubt slower than C regarding compilation and execution of the code. Couple that with the verbosity of Java codes and you’ll realize the amount of time you can save if you opt for CPP. During coding contests, you need to compile and run programs many times before you reach the desired output. Java takes a lot of time in this aspect, while C++ is a lot slower. Therefore, in limited time contests, C++ can help save time. However, many coding contests today provide different time limits for Java and C++ with that for Java being on a slightly higher end than C++. So, even if you choose Java as your sword, you won’t lose out on too much. Just be thorough in whichever language you choose.

Wrapping it up, C++ is till date the most preferred language followed by Java for competitive programming. However, ardent Java coders still use Java and beat other coders fair and square. C++ being more popular doesn’t make it the one for you. Eventually, it all boils down to your comfort and your needs. If you’ve been coding in C/C++, you shouldn’t switch to Java just because of its exception handling capabilities. Similarly, if you have a Java background and are competent at it, C++ shouldn’t be your choice only because of its benefits. Being confident in what language you chose is the key along with rigorous practice. We at Coding Ninjas make sure you don’t lack in either – come, join us, and see yourself excel!