diff --git a/cxy_opt/render.h b/cxy_opt/render.h
new file mode 100644
index 0000000..c7200a8
--- /dev/null
+++ b/cxy_opt/render.h
@@ -0,0 +1,40 @@
+#ifndef __RENDER_H
+#define __RENDER_H
+#pragma GCC optimize ("O3")
+#include <stdlib.h>
+#include <time.h>
+
+#define MAT_SIZE 514
+#define RAND_SEED 114514
+void Render(float a[][MAT_SIZE]);
+void Print(float a[][MAT_SIZE]);
+
+void Render(float a[][MAT_SIZE])
+{
+	srand(RAND_SEED);
+	int i, j;
+	for(i=0; i<MAT_SIZE; i++)
+	for(j=0; j<MAT_SIZE; j++) {
+		a[i][j] = (float)rand() / (float)RAND_MAX;
+	}
+}
+
+void Print(float a[][MAT_SIZE])
+{
+	printf("Matrix with Size=(%d,%d)\n", MAT_SIZE, MAT_SIZE);
+	printf("%5.1f %5.1f %5.1f  ...  %5.1f %5.1f %5.1f\n", a[0][0], a[0][1], a[0][2], 
+		a[0][MAT_SIZE-3], a[0][MAT_SIZE-2], a[0][MAT_SIZE-1]);
+	printf("%5.1f %5.1f %5.1f  ...  %5.1f %5.1f %5.1f\n", a[1][0], a[1][1], a[1][2], 
+		a[1][MAT_SIZE-3], a[1][MAT_SIZE-2], a[1][MAT_SIZE-1]);
+	printf("%5.1f %5.1f %5.1f  ...  %5.1f %5.1f %5.1f\n", a[2][0], a[2][1], a[2][2], 
+		a[2][MAT_SIZE-3], a[2][MAT_SIZE-2], a[2][MAT_SIZE-1]);
+	printf("   ...   ...   ...   ...   ...   ...   ... \n");
+	printf("%5.1f %5.1f %5.1f  ...  %5.1f %5.1f %5.1f\n", a[MAT_SIZE-3][0], a[MAT_SIZE-3][1], a[MAT_SIZE-3][2], 
+		a[MAT_SIZE-3][MAT_SIZE-3], a[MAT_SIZE-3][MAT_SIZE-2], a[MAT_SIZE-3][MAT_SIZE-1]);
+	printf("%5.1f %5.1f %5.1f  ...  %5.1f %5.1f %5.1f\n", a[MAT_SIZE-2][0], a[MAT_SIZE-2][1], a[MAT_SIZE-2][2], 
+		a[MAT_SIZE-2][MAT_SIZE-3], a[MAT_SIZE-2][MAT_SIZE-2], a[MAT_SIZE-2][MAT_SIZE-1]);
+	printf("%5.1f %5.1f %5.1f  ...  %5.1f %5.1f %5.1f\n", a[MAT_SIZE-1][0], a[MAT_SIZE-1][1], a[MAT_SIZE-1][2], 
+		a[MAT_SIZE-1][MAT_SIZE-3], a[MAT_SIZE-1][MAT_SIZE-2], a[MAT_SIZE-1][MAT_SIZE-1]);
+}
+#endif
+