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static void Main(string[] args) {
Console.Write("moi nhap so phan tu cua mang: ");
int n = int.Parse(Console.ReadLine()); int[] a = new int[n]; NhapMang1(a); Output(a); Console.WriteLine(); NhapMang2(out a); Output(a); Console.WriteLine(); int[] arr = NhapMang3(); Output(arr); bt2(a);
Console.WriteLine("tong gia tri cac phan tu la" + bt3(a));
Console.WriteLine("vi tri cua phan tu co gia tri bang x: "+bt4(a));
Console.WriteLine("vi tri phan tu co gia tri lon nhat trong mang la: "+bt5());
Console.WriteLine("so phan tu co gia tri lon hon 0 la: "+bt6(a)); bt7(a); bt8(a); Console.ReadKey(); }
static void NhapMang1(int[] a) {
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); } }
static void NhapMang2(out int[] a) {
Console.Write("moi nhap so phan tu cua mang: ");
int n = int.Parse(Console.ReadLine()); a = new int[n];
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); } } static int[] NhapMang3() {
Console.Write("moi nhap so phan tu cua mang: ");
int n = int.Parse(Console.ReadLine()); int[] a = new int[n];
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); }; return a; } static void Output(int[] a) {
for (int i = 0; i < a.Length; i++) { Console.Write(a[i] + " "); } } static void bt2(int[] a) {
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); };
for (int i = 0; i < a.Length; i++) { Console.Write(a[i] + " "); }; Console.WriteLine(); } static int bt3(int[] a) { int sum = 0;
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); };
for (int i = 0; i < a.Length; i++) { sum += a[i]; }; return sum; } static int bt4(int[] a) {
Console.WriteLine("moi nhap x: ");
int x = int.Parse(Console.ReadLine()); int i = 0; int kq = -1;
for (i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); };
for (i = 0; i < a.Length; i++) { if (a[i] == x) { kq = i; break; } } return kq; } static int bt5() {
Console.Write("moi nhap so phan tu cua mang: ");
int n = int.Parse(Console.ReadLine()); double[] a = new double[n]; double max = a[0]; int i; int vitri = 0;
for (i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = double.Parse(Console.ReadLine()); };
for (i = 0; i < a.Length; i++) { if (max <= a[i]) { max = a[i]; vitri = i; } } return vitri; } static int bt6(int[] a) { int i = 0; int count = 0;
for (i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); if (a[i] >0) { count = count + 1; } }; return count; } static void bt7(int[] a) {
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); }; int c;
for (int i = 0; i < a.Length - 1; i++) {
for (int j = i + 1; j < a.Length; j++) { if (a[i] > a[j]) { c = a[i]; a[i] = a[j]; a[j] = c; } } };
for (int i = 0; i < a.Length; i++)
{ Console.Write(a[i] + " "); } } static void bt8(int[] a) {
Console.Write("moi nhap k: ");
int k = int.Parse(Console.ReadLine());
Console.Write("moi nhap l: ");
int l = int.Parse(Console.ReadLine());
while (k < 0 | l<0 | k>a.Length | l> a.Length) {
Console.Write("moi nhap k: ");
k = int.Parse(Console.ReadLine());
Console.Write("moi nhap l: ");
l = int.Parse(Console.ReadLine()); };
for (int i = 0; i < a.Length; i++) { Console.Write($"a[{i}]: ");
a[i] = int.Parse(Console.ReadLine()); }; int c;
for (int i = 0; i < a.Length - 1; i++) {
for (int j = i + 1; j < a.Length; j++) { if (a[i] > a[j]) { c = a[i]; a[i] = a[j]; a[j] = c; } } };
for (int i = 0; i < a.Length; i++) {
if (i >= k & i <= l) { Console.Write(a[i] + " "); }; } }