IOI 2003
All 4 IOI tasks from 2003, organized as individual solution pages.
Problem set
Each entry below goes straight to the public problem page, with the statement, editorial, code, and raw resources kept together.
Amazing (Maze Exploration)
Problem Statement Summary This is an interactive problem. You are placed in an R C grid maze whose structure is unknown. At each step you can query which directions (N, S, E, W) are open from the current cell. Navigat...
Boundary (Convex Hull)
Problem Statement Summary Given N points (N 10^5) in the plane, compute the convex hull. Output the hull vertices in order, together with the perimeter, area, and the number of input points lying on the hull boundary....
Comparing Substrings
Problem Statement Summary Given a string S of length N (N 10^5) and Q queries (Q 10^5), each query specifies two substrings S[a a + -1] and S[b b + -1] and asks for their lexicographic ordering (equal, less than, or g...
Reverse
Problem Statement Summary Given a sequence of N integers and Q reverse operations, each specifying a range [l, r], apply all reversals in order and output the final sequence. A secondary variant asks for the minimum n...