HDOJ2084

#include 
#include 

int N,M;
int main(int argc, char *argv[]) {
	while(scanf("%d",&M)==1)
	{
		while(scanf("%d",&N) != EOF)
		{
		int A[N][N];
		int B[N+1][N+1];
		int i,j;
		for(i = 0; i= 0; i--)
		for(j = 0; j<=i; j++)
		{
			if(B[i+1][j]>=B[i+1][j+1])
				B[i][j] = A[i][j] + B[i+1][j];
			else
				B[i][j] = A[i][j] +B[i+1][j+1];
		}
		printf("%d\n",B[0][0]);
		}
	}
	
	return 0;
}

解题思路:上一层的最大值取决于下层的最大值;用数组A[N]记录每一个节点;B[N+1]记录过程中的最长路径；注意bottom up！