#include<stdio.h>// de su dung printf va scanf
 #include<conio.h>// ket thuc ham bang getch();
 #define MAX 100 // gia tri lon la 100
//___________________________________________________________________________________________//
/*
	Su dung 2 thu vien chinh.
*/
//______________________________________________________________________//
/*
	Khai bao danh sach struct

*/


//________________________________________________________________________//
/*
	Khai bao chuong trinh con
*/
//===============================//
// ham con nhap 1 mang
//===== so luong phan tu mang =========//
 
void nhapsoluongphantu( int  &n )
{

do{
		printf("Moi ban nhap so luong phan tu cua mang, chu y khong am: ");
		scanf("%d", &n);
  } while (n<=0 || n>100); // nhap vao gia tri sai voi dieu kien se phai nhap lai
}
 /*-----------------------------------------
 // ham nhap gia tri cho tung phan tu trong mang 
 */
 void nhapmang(int a[],int n)
 {
 	for(int i=0;i<n;i++)/// khoi tao vong lap for voi i= 0 , vi mang bat dau tu thu 0 , i<n vi phan tu cuoi cung la bang n-1
 	{
 	 	printf("a[%d]=",i);
 	 	scanf("%d",&a[i]);
	}
 }
 /*-----------------------------------------
 // ham xuat cac phan tu cua mang ra man hinh
 */
 void xuatmang(int a[],int n)
{
 	printf("\n Mang gom cac phan tu :\n");
    for(int i=0;i<n;i++) /// khoi tao vong lap for voi i= 0 , vi mang bat dau tu thu 0 , i<n vi phan tu cuoi cung la bang n-1
   {
	 printf("%5d",a[i]);
   }
}
/*-----------------------------------------
 // ham tim vi tri phan tu duong dau tien
 */
int timduongdau(int a[],int n)
{
	int flag = -1 ;
	for(int i=0;i<n;i++)/// khoi tao vong lap for voi i= 0 , vi mang bat dau tu thu 0 , i<n vi phan tu cuoi cung la bang n-1
	{
		
		if(a[i]>0)// de kiem tra phan tu duong trong mang
	{
	flag =1;
     return 0;
	}
}
// ket thuc vong for ,vna khong thay doi flag, nghia la tim khong thay
if(flag = -1)
 {
	return -1 ;
 } 
}
/*-----------------------------------------
 // ham tim vi tri phan tu duong cuoi trong mang
 */
 int PhanTuDuongCuoiCungTrongMang(int a[],int n)
{
	int flag = -1; // flag xac dinh ton tai so duong trong mang hay ko?, hien tai la -1, ko biet.
	for( int i=n-1; i>=0;i-- ) // chay nguoc tu cuoi mang ve 0, cuoi mang la n-1, ve 0 nen >=0
	{
		if( a[i]>0 ) // day la dieu kien phan tu duong
		{
			flag = 1;
			return i;
		}
	}
	//// ket thuc vong for, van ko thay doi flag, nghia la tim ko thay
	if( flag == -1 )
	{
		return -1;
	}
}
//=============================================//
int GiaTriLonNhatTrongMang( int a[], int n )
{
	int Max = a[0]; // gan thang a[0] la max, so sanh nhung vi tri con lai xem co phan tu nao lon hon Max ko?
	for( int i = 1; i < n ; i++ ) // chay tu vi tri 1, cho den n-1. ko xet vi tri 0
	{
		if( a[i] > Max ) // neu no cao hon thang Max, thi no se danh vi tri Max
		{
			Max= a[i]; // chu mung dong chi a[i] da danh ngoi vi quan quan
		}

	}
	////// ket thuc vong fot, da xac dinh dc Max
	return Max;
	
}

//=======Xuat vi tri Max, co the co nhieu vi tri Max======================//
void ViTriMaxTrongMang( int a[], int n )
{
	int Max = GiaTriLonNhatTrongMang( a,n );
	printf("\nNhung vi tri ma gia tri lon nhat trong mang: ");
	for( int i = 0; i < n; i++  ) // lan nay chay i tu 0 toi n-1, vi Max co the o vi tri bat ky trong mang.
	{
		if( a[i] == Max )
		{
			printf("%5d",i+1);
		}
	}
}
int main()
{
	int a[100];// Mang kieu so nguyen toi da 100 phan tu
	int n=0;//n la ten bien soluongphantu , so luong la so nguyen khoi tao bang 0
   nhapsoluongphantu(n);
    nhapmang(a,n);
    xuatmang(a,n);
    int vitri=timduongdau(a,n);
	if(vitri==-1)
	{
	printf("\nKhong co phan tu duong trong mang!");
	}
	else
	{
		printf("\nPhan tu duong dau tien trong mang la: %d dung o vi tri so %d",a[vitri], vitri+1 );
	}
int vitriduongcuoi = PhanTuDuongCuoiCungTrongMang (a,n);
	if( vitriduongcuoi == -1  )
	{
		printf("\nKhong co phan tu duong trong mang!");
	}
	else
	{
		printf("\nPhan tu duong cuoi cung trong mang la: %d dung o vi tri so %d", a[vitriduongcuoi], vitriduongcuoi+1 );
	}
	ViTriMaxTrongMang(a,n);
	getch ();
}