#include<stdio.h>
void nhapmang(int a[20][20], int n, int m)
{
	for (int i = 0; i < n; i++)
	for (int j = 0; j < m; j++)
	{
		printf("a[%i][%i] = ", i, j); scanf("%i", &a[i][j]);
	}
}
void sapxep(int a[], int m)
{
	int n = m;
	for (int j = 0; j < n; j++){
		int max = 0, vitri = 0;
		for (int i = 0; i < m; i++){                           //tim max, cho no vao vitri cuoi dong va lap lai
			if (a[i]>max){ max = a[i]; vitri = i; }
			if (i == m - 1){
				a[vitri] = a[i];
				a[i] = max;
				m--;
			}
		}
	}
}
void main()
{
	int a[20][20],n,m;
	int b[400],h=0;
	while (1){
		printf("Nhap so dong va so cot cua mang: "); scanf("%i %i", &n, &m);
		if (m<1 || n<1 || m>20 || n>20)continue;
		break;
	}
	nhapmang(a, n, m);
	for (int i = 0; i < n;i++)
	for (int j = 0; j < m; j++){
		b[h] = a[i][j];
		h++;
	}
	sapxep(b, h+1);
	h = 0;
	for (int i = 0; i < n; i++)
	for (int j = 0; j < m; j++){
		a[i][j]=b[h];
		h++;
	}
	printf("Ma tran sau khi sap xep: \n");
	for (int i = 0; i < n; i++){
		for (int j = 0; j < m; j++){ printf("%i   ", a[i][j]); }
		printf("\n");
	}
}