add evaluation example

README.md

@@ -56,8 +56,72 @@ To validate the reliability of this benchmark, we run both correct and represent
 
 ```python
 from datasets import load_dataset
+from pathlib import Path
+import os
 
 dataset = load_dataset("stepfun-ai/CF-Div2-Stepfun", name="release_v1", split="test")
+
+# An evaluation example is given below for problem id=1:
+# make sure you have prepared necessary checkers first
+# here the checker used is "ncmp" as an example, for other problems inspect the marked checker name
+# > git clone https://github.com/MikeMirzayanov/testlib.git
+# > g++ -std=c++20 -Wall -Wextra --static -I testlib/ testlib/checkers/ncmp.cpp -o ncmp
+assert dataset[0]["problem_id"] == "codeforces/2020A"
+assert dataset[0]["checker"] == "ncmp"
+
+# prepare a submission code
+submission_code = \
+r"""
+#include <bits/stdc++.h>
+using namespace std;
+ 
+int find_min_oper(int n, int k){
+	if(k == 1) return n;
+	int ans = 0;
+	while(n){
+		ans += n%k;
+		n /= k;
+	}
+	return ans;
+}
+
+int main()
+{
+	int t;
+	cin >> t;
+	while(t--){
+		int n,k;
+		cin >> n >> k;
+		cout << find_min_oper(n,k) << "\n";
+	}
+	return 0;
+}
+"""
+
+eval_dir = Path("./eval_test")
+eval_dir.mkdir(exist_ok=True)
+with open(eval_dir / "code.cpp", "w") as fout:
+    fout.write(submission_code)
+
+# run compilation
+ret = os.system(f"g++ -std=c++20 -fno-asm -fsanitize=bounds -fno-sanitize-recover=bounds -static -O2 -DONLINE_JUDGE -o {eval_dir / 'code.exe'} {eval_dir / 'code.cpp'}")
+assert ret == 0
+
+for idx, test_case in enumerate(dataset[0]["test_cases"]):
+
+    with open(eval_dir / f"{idx}.in", "w") as fout:
+        fout.write(test_case["input"])
+    with open(eval_dir / f"{idx}.ans", "w") as fout:
+        fout.write(test_case["output"])
+
+    # run code
+    # apply more time / space constraints if you like
+    ret = os.system(f"{eval_dir / 'code.exe'} < {eval_dir}/{idx}.in > {eval_dir}/{idx}.out")
+    assert ret == 0
+
+    # run checker
+    ret = os.system(f"./ncmp {eval_dir}/{idx}.in {eval_dir}/{idx}.out {eval_dir}/{idx}.ans")
+    assert ret == 0
 ```
 
 ## Evaluation Details
@@ -85,7 +149,7 @@ You are a coding expert. Given a competition-level coding problem, you need to w
 The compilation and execution commands for C++, Python, Java are given below:
 
 ```
-g++ -std=c++20 -fno-asm -fsanitize=bounds -fno-sanitize-recover=bounds –static -O2 -DONLINE_JUDGE -o code.exe code.cpp
+g++ -std=c++20 -fno-asm -fsanitize=bounds -fno-sanitize-recover=bounds -static -O2 -DONLINE_JUDGE -o code.exe code.cpp
 ./code.exe
 ```