diff --git a/Lab1/README.md b/Lab1/README.md
index 8a0e781f..1c754ff4 100644
--- a/Lab1/README.md
+++ b/Lab1/README.md
@@ -122,7 +122,7 @@ Your program should be able to:
 2. Successfully solve the puzzles in the input file, and output the results in the format described before.
 3. Use multiple threads/processes to make use of most of your machine's CPU cores.
 
-\[Tips\]: 1) Use event queue to dispatch tasks and merge results to/from worker threads. 2) Dynamically detect how many CPU cores are there on your machine, in order to decide how many threads/processes your program uses. 3) Be careful about the contention among multiple threads/processes
+\[Tips\]: 1) Use event **queue** to dispatch tasks and merge results to/from worker threads. 2) Dynamically detect how many CPU cores are there on your machine, in order to decide how many threads/processes your program uses. 3) Be careful about the contention among multiple threads/processes
 
 ##### 3.1.3.2 Advanced version
 
diff --git a/Lab1/src/Sudoku/Makefile b/Lab1/src/Sudoku/Makefile
index c5e2a079..5b6aef98 100644
--- a/Lab1/src/Sudoku/Makefile
+++ b/Lab1/src/Sudoku/Makefile
@@ -1,7 +1,7 @@
 CXXFLAGS+=-O2 -ggdb -DDEBUG
 CXXFLAGS+=-Wall -Wextra
 
-all: sudoku
+all: sudoku_solve
 
-sudoku: main.cc neighbor.cc sudoku_basic.cc sudoku_min_arity.cc sudoku_min_arity_cache.cc sudoku_dancing_links.cc
+sudoku_solve: sudoku_solve.cc neighbor.cc sudoku_basic.cc sudoku_min_arity.cc sudoku_min_arity_cache.cc sudoku_dancing_links.cc
 	g++ -O2 -o $@ $^
diff --git a/Lab1/src/Sudoku/Makefile0 b/Lab1/src/Sudoku/Makefile0
new file mode 100644
index 00000000..c5e2a079
--- /dev/null
+++ b/Lab1/src/Sudoku/Makefile0
@@ -0,0 +1,7 @@
+CXXFLAGS+=-O2 -ggdb -DDEBUG
+CXXFLAGS+=-Wall -Wextra
+
+all: sudoku
+
+sudoku: main.cc neighbor.cc sudoku_basic.cc sudoku_min_arity.cc sudoku_min_arity_cache.cc sudoku_dancing_links.cc
+	g++ -O2 -o $@ $^
diff --git a/Lab1/src/Sudoku/main.cc b/Lab1/src/Sudoku/main.cc
index 4ed2f3a5..aa0730e2 100644
--- a/Lab1/src/Sudoku/main.cc
+++ b/Lab1/src/Sudoku/main.cc
@@ -55,3 +55,4 @@ int main(int argc, char* argv[])
   return 0;
 }
 
+// This is a test
\ No newline at end of file
diff --git a/Lab1/src/Sudoku/sudoku b/Lab1/src/Sudoku/sudoku
new file mode 100644
index 00000000..5fb59225
Binary files /dev/null and b/Lab1/src/Sudoku/sudoku differ
diff --git a/Lab1/src/Sudoku/sudoku_solve b/Lab1/src/Sudoku/sudoku_solve
new file mode 100644
index 00000000..96819086
Binary files /dev/null and b/Lab1/src/Sudoku/sudoku_solve differ
diff --git a/Lab1/src/Sudoku/sudoku_solve.cc b/Lab1/src/Sudoku/sudoku_solve.cc
new file mode 100644
index 00000000..53fafcbf
--- /dev/null
+++ b/Lab1/src/Sudoku/sudoku_solve.cc
@@ -0,0 +1,52 @@
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/time.h>
+
+#include "sudoku.h"
+
+int64_t now()
+{
+  struct timeval tv;
+  gettimeofday(&tv, NULL);
+  return tv.tv_sec * 1000000 + tv.tv_usec;
+}
+
+int main(int argc, char const *argv[])
+{
+	init_neighbors();
+
+	FILE* fp = fopen(argv[1], "r");
+	char puzzle[128];
+	int total_solved = 0;
+	int total = 0;
+	bool (*solve)(int) = solve_sudoku_basic;
+
+	solve = solve_sudoku_min_arity;
+	// solve = solve_sudoku_min_arity_cache;
+	// solve = solve_sudoku_dancing_links;
+
+	int64_t start = now();
+	// 一直读取, 读到 puzzle 中
+	while (fgets(puzzle, sizeof puzzle, fp) != NULL) {
+		if (strlen(puzzle) >= N) {
+			++total;
+			input(puzzle);
+			init_cache();
+
+			if (solve(0)) {
+				++total_solved;
+				if (!solved()) assert(0);
+			}
+			else {
+				printf("No: %s", puzzle);
+			}
+		}
+	}
+	int64_t end = now();
+	double sec = (end - start)/1000000.0;
+	printf("%f sec %f ms each %d\n", sec, 1000*sec/total, total_solved);
+
+	return 0;
+}
\ No newline at end of file