#include<stdio.h>
#include<conio.h>
#define MAX 100
void NhapMang(int a[], int n)
{
	for (int i = 0; i < n; i++)
	{
		printf("\nNhap vao phan tu a[%d] = ", i);
		scanf_s("%d", &a[i]);
	}
}
void XuatMang(int a[], int n)
{
	for (int i = 0; i < n; i++)
	{
		printf("%4d", a[i]);

	}
}
void HoanVi(int &a, int &b)
{
	int temp = a;
	a = b;
	b = temp;
}
void SapXepTangDan(int a[], int n)
{
	
	for (int i = 0; i < n - 1; i++)
	{
	    int min = i;
		for (int j = i + 1; j < n; j++)
		{
			if (a[min] > a[j])
			{
				min = j;
			}
		}
		if (min != i)
		{
			HoanVi(a[i], a[min]);
		}
	}
}
int main()
{
	int n;
	do
	{
		printf("\nNhap vao so luong phan tu cua mang ");
		scanf_s("%d", &n);
		if (n < 0 || n > MAX)
			printf("\nSo luong phan tu khong hop le. Xin kiem tra lai !");
	} while (n < 0 || n > MAX);

	int a[MAX];
	NhapMang(a, n);
	XuatMang(a, n);
	SapXepTangDan(a, n);
	printf("\nSap xep tang dan: ");
	XuatMang(a, n);

	_getch();
	return 0;
}

Line 17: error: conio.h: No such file or directory
In function 'NhapMang':
Line 6: error: 'for' loop initial declaration used outside C99 mode
In function 'XuatMang':
Line 14: error: 'for' loop initial declaration used outside C99 mode
t.c: At top level:
Line 20: error: expected ';', ',' or ')' before '&' token
In function 'SapXepTangDan':
Line 29: error: 'for' loop initial declaration used outside C99 mode
Line 32: error: 'for' loop initial declaration used outside C99 mode