refactor(structure): normalize folder names with leading zeros for consistency

- Renamed all folders from format NEx (e.g., 1Ex, 2Ex...) to 0NEx (01Ex, 02Ex, etc.)
- Updated subdirectories and files accordingly
- Removed old main Makefile and tasks (a01.c–a09.c, solve.c, io_status.h), likely obsolete
- Cleaned up deprecated task binaries and configs

2025.03.07/01Ex/array_io.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include "array_io.h"
+
+io_status read_sq_matrix(double *a, int n, const char *name)
+{
+	int i, j;
+	FILE *fp;
+	if (!(fp = fopen(name, "r"))) return ERROR_OPEN;
+	for (i = 0; i < n; i++)
+		for (j = 0; j < n; j++)
+			if (fscanf(fp, "%lf", a + i * n + j) != 1) 
+				{fclose(fp); return ERROR_READ;}
+	fclose(fp);
+	return SUCCESS;
+}
+
+void print_sq_matrix(const double *a, int n, int p)
+{
+	int np = (n > p ? p : n);
+	int i, j;
+
+	for (i = 0; i < np; i++)
+	{
+		for (j = 0; j < np; j++)
+			printf(" %10.3e", a[i * n + j]);
+		printf("\n");
+	}
+}
+
+void init_sq_matrix(double *a, int n, int k)
+{
+	double (*q)(int, int, int, int);
+	double (*f[])(int, int, int, int) = {f1, f2, f3, f4};
+	int i, j;
+	q = f[k-1];
+	for (i = 0; i < n; i++)
+		for (j = 0; j < n; j++)
+			a[i * n + j] = q(n, n, i+1, j+1);
+}