#include<stdio.h>
#include<conio.h>
#include<math.h>
#define MAX 100
void NhapMaTran(int a[][MAX], int &n)
{
	do
	{
		printf("\nNhap n: ");
		scanf("%d", &n);
		if(n < 1 || n > MAX)
		{
			printf("\nSo phan tu khong hop le. Xin kiem tra lai !");
		}
	}while(n < 1 || n > MAX);

	for(int i = 0; i < n; i++)
	{
		for(int j = 0; j < n; j++)
		{
			printf("\nNhap vao a[%d][%d] = ", i, j);
			scanf("%d", &a[i][j]);
		}
	}
}

void XuatMaTran(int a[][MAX], int n)
{
	for(int i = 0; i < n; i++)
	{
		for(int j = 0; j < n; j++)
		{
			printf("%4d",a[i][j]);
		}
		printf("\n\n");
	}
}

void Tim2GiaTriGanNhauNhat(int a[][MAX], int n, int &x1, int &x2)
{
	int KhoangCach = abs(a[0][0] - a[0][1]); // khởi tạo
	x1 = a[0][0];
	x2 = a[0][1];
	int i, j;
	for(i = 0; i < n; i++)
	{
		for(j = 0; j < n; j++)
		{
			if(i == n - 1 && j == n - 1)  // Nếu ma trận chỉ có 1 phần tử
			{
				break;
			}
			for(int k = i; k < n; k++)
			{
				for(int h = 0; h < n; h++)
				{
					if(k == i && h <= j)
					{
						continue;
					}
					if(KhoangCach > abs(a[i][j] - a[k][h]))
					{
						KhoangCach = abs(a[i][j] - a[k][h]);
						x1 = a[i][j];
						x2 = a[k][h];
					}
				}
			}
		}
	}
}
int main()
{
	int a[MAX][MAX], n, x1, x2;
	NhapMaTran(a,n);
	XuatMaTran(a,n);

	Tim2GiaTriGanNhauNhat(a, n, x1, x2);
	printf("\n2 Gia tri gan nhau nhat la %d va %d", x1, x2);
	
	getch();
	return 0;
}

Line 17: error: conio.h: No such file or directory
Line 5: error: expected ';', ',' or ')' before '&' token
In function 'XuatMaTran':
Line 29: error: 'for' loop initial declaration used outside C99 mode
Line 31: error: 'for' loop initial declaration used outside C99 mode
t.c: At top level:
Line 39: error: expected ';', ',' or ')' before '&' token