Add input validation command

[kiritofeng]

Add to init.yml

validator:
  source: validate.cpp
  language: CPP14
  time: 2
  memory: 65536

[codecov-commenter]

Codecov Report

Attention: 12 lines in your changes are missing coverage. Please review.

Comparison is base (e2b6533) 82.71% compared to head (73a2ade) 82.98%.
Report is 4 commits behind head on master.

Files	Patch %	Lines
dmoj/problem.py	81.48%	5 Missing ⚠️
dmoj/contrib/default.py	83.33%	2 Missing ⚠️
dmoj/contrib/testlib.py	77.77%	2 Missing ⚠️
dmoj/contrib/base.py	93.75%	1 Missing ⚠️
dmoj/contrib/coci.py	90.00%	1 Missing ⚠️
dmoj/contrib/peg.py	87.50%	1 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1093      +/-   ##
==========================================
+ Coverage   82.71%   82.98%   +0.26%     
==========================================
  Files         141      143       +2     
  Lines        5310     5488     +178     
==========================================
+ Hits         4392     4554     +162     
- Misses        918      934      +16     

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[kiritofeng]

Sample output:

dmoj> validate echo
Validating problem echo...
Batch #1
  Test case  1 AC
  Test case  2 IR (N != 1 in batch 1)
  Test case  3 IR (N not in (1, 2, 4))
  Test case  4 IR (N != 1 in batch 1)
Batch #2
  Test case  5 AC
  Test case  6 AC
  Test case  7 IR (N not in (1, 2, 4))
  Test case  8 AC
  Test case  9 IR (ValueError)
Problem echo failed.


Test complete.
A total of 1 problem(s) have invalid input

Validator:

import sys
batch = int(sys.argv[1])
N = int(input())
if N not in (1,2,4):
    print('N not in (1, 2, 4)')
    sys.exit(1)
elif N != 1 and batch == 1:
    print('N != 1 in batch 1')
    sys.exit(1)

init.yml:

test_cases:
- batched:
  - {in: 1.txt, out: 1.txt}
  - {in: 2.txt, out: 2.txt}
  - {in: 3.txt, out: 3.txt}
  - {in: 4.txt, out: 4.txt}
  points: 1
- batched:
  - {in: 1.txt, out: 1.txt}
  - {in: 2.txt, out: 2.txt}
  - {in: 3.txt, out: 3.txt}
  - {in: 4.txt, out: 4.txt}
  - {in: a.txt, out: a.txt}
  points: 1
validator:
  source: validate.py
  language: PY3
  time_limit: 2
  memory_limit: 65536
  read_feedback_from: stdout

(note that x.txt is a text file contain only x)

[Xyene]

LGTM

[Riolku]

Yay for sanity - thanks for fixing it up.