POJ1088 滑雪

思考：動態規劃，填表格。

#include 
#include 
#include 
#include 
#include 

using namespace std;
const int maxn = 110;

struct info {
	int row;
	int col;
	int value;
};
int table[maxn][maxn]; //dp
int data[maxn][maxn];// input data

vector V;
int gr, gc;
int ans;

bool cmp(info x, info y) {
	if(x.value > y.value) return true;
	else return false;
}

void update(int x, int y)
{
	if(x > 1) {
		if(data[x][y] < data[x-1][y])
			table[x][y] = max(table[x][y], table[x-1][y]+1);
	}
	if(y > 1) {
		if(data[x][y] < data[x][y-1])
			table[x][y] = max(table[x][y], table[x][y-1]+1);
	}
	if(x < gr) {
		if(data[x][y] < data[x+1][y])
			table[x][y] = max(table[x][y], table[x+1][y]+1);
	}
	if(y < gc) {
		if(data[x][y] < data[x][y+1])
			table[x][y] = max(table[x][y], table[x][y+1]+1);
	}
	if(table[x][y] > ans) ans = table[x][y];
}

int work()
{
	int bound = (int)V.size();
	info now;
	int x, y, value;
	for(int i = 0; i < bound; i++) {
		now = V[i];
		x = now.row; y = now.col; value = now.value;
		table[x][y] = 1;
		update(x, y);
	}
	return ans;
}

int main()
{
	int tmp;
	info read;
	while(scanf("%d%d", &gr, &gc) != EOF) {
		memset(table, 0, sizeof(table));
		ans = 0;
		V.clear();
		for(int i = 1; i <= gr; i++) {
			for(int j = 1; j <= gc; j++) {
				scanf("%d", &tmp);
				read.row = i; read.col = j; read.value = tmp;
				V.push_back(read);
				data[i][j] = tmp;
			}
		}
		sort(V.begin(), V.end(), cmp);
		int result = work();
		printf("%d\n", result);
	}
	return 0;
}