This is a compiler project behind Procon Input.

If you play competitive programming, you should be bothered parsing the input.

The syntax of the input is usually something like this:

N
A1 A2 A3 ... AN

You may be parsing the input by writing boilarplate code but imagine what if you can parse the input from the syntax itself.

n: int
a: [int; n]

This is what Procon Input does.

Root := Line in-between ‘\n’
Line := Definition in-between ‘,‘
Definition := Var : Type

UnitType := int | int0 | float | str
Array := [UnitType; Len]
List := [UnitType]

TupleElem := UnitType | Array | List
Tuple := (TupleElem in-between ‘,’)
TupleLike := Array | List | Tuple

Matrix := [TupleLike; Len]
Type := UnitType | TupleLike | Matrix

4 3
1 2 3
4 5 6
7 8 9
10 11 12

n: int, m: int
mat: [[int;m]; n]

int0 interprets 1-indexed number to a 0-indexed number.

4
2 2 3
1 4
0
0

n: int
g: [[int0]; n]

graph TD
  v1(1) --> v2(2)
  v1 --> v3(3)
  v2 --> v4(4)

4 3
1 2 1.0
1 3 1.5
2 4 2.5

n_v: int, n_e: int
e: [(int0, int0, float); n_e]

graph TD
  v1(1) -->|1.0| v2(2)
  v1 -->|1.5| v3(3)
  v2 -->|2.5| v4(4)

Single element tuple (A) is interpreted as A.

3
10
20
40

n: int
a: [(int); n]

• Supported languages: Python, C++, Nim, Ruby, Java, C#, Rust, Kotlin, Go, Swift

a: [float; 100000]

e: [[int; 2]; 100000]

a: [(str); 1000]

graph LR
  P(Parser)
  subgraph codegen
    EC(Common Layer)
    EL(Language Specific)
  end
  Input -->|Text| P -->|AST| EC --> EL -->|Text| Output

• proconio
• proconIO.jl

Use test-runner command in dev container.

$ ./dev
# cargo run --package test-runner -- test

$ ./dev
# cargo run --package test-runner -- bench

Akira Hayakawa (@akiradeveloper)