Indian Computing Olympiad (ICO) 2025: Complete Guide

What is ICO?

The Indian Computing Olympiad (ICO) is India's top-tier algorithm and programming contest organized annually by IARCS iarcs.org.in. Its purpose is to identify talented school students and select four to represent India at the International Olympiad in Informatics (IOI).

Eligibility & Registration

• Open to: All students enrolled in school through Class 12 in the academic year of participation.
• No age limit, but Class 12 completers are not eligible.
• Registration: Opens around October for the next cycle (e.g., ICO–2026 in Oct 2025).

Exam Stages & Pattern

1. Zonal Round (First Stage)

• ZIO (Zonal Informatics Olympiad)

  • Pen-and-paper written exam
  • ~4 problems, 12 sub-parts, 3 hours, 80 marks.

• ZCO (Zonal Computing Olympiad)

  • Online programming contest (C++, Java, Python)
  • Typically 2 algorithmic problems, timed.

• Advancement: Qualify via either ZIO or ZCO.

2. INOI (Indian National Olympiad in Informatics)

• Programming exam (C++ only)
• ~2 complex problems, 3 hours.

3. IOITC (International Olympiad in Informatics Training Camp)

• ~30 top INOI performers attend 7-day training (June 2025).

4. IOI Selection

• Top 4 from IOITC form Team India for IOI (Bolivia, July 27–August 3, 2025).

Syllabus & Preparation

ZIO & ZCO Topics

• Basic algorithms and data structures: sorting, searching, recursion, dynamic programming, graphs .
• Discrete mathematics and problem-solving logic .

INOI & IOITC

• Advanced algorithmic concepts per IOI syllabus:

  • Graph theory, DP, greedy techniques, advanced data structures, combinatorics.

Prep Resources

• IARCS Online Materials: targeted topic notes and problem archive.
• Practice Platforms: IARCS judge, CodeChef, CodeDrills, Commonlounge.
• Books: Algorithm Design (Kleinberg–Tardos), Introduction to Algorithms (CLRS), Competitive Programming (Halim), Programming Challenges (Skiena).

Marking Scheme & Logistics

• ZIO: Scored per sub-part; full marks typically 80–100.
• ZCO & INOI: Partial scoring based on successful test cases.
• INOI onwards: C++ only.
• No negative marking unless specified.

Rewards & Opportunities

• Medals at INOI: ~60 awardees (11 Gold, 19 Silver, 30 Bronze).
• IOITC admission equals fast-track to IOI.
• Institutional perks: CMI, IIIT Delhi/Hyderabad, IITs, Amrita, IIIT‑Hyderabad etc. offer direct admissions or bonus points.
• International exposure: IOI + APIO selection; national achievements bolster competitive programming careers.

Timeline Summary

Quick Facts

• Eligibility: Any school student up to Class 12
• Stages: ZIO/ZCO → INOI → IOITC → IOI
• Programming Languages: C++, Java, Python (ZCO); C++ only (INOI+)
• Preparation: Algorithms + data structures + practice on judge platforms
• Institutions: Offers include CMI, IIITs, IITs via olympiad streams