hdu2084数塔

http://acm.hdu.edu.cn/showproblem.php?pid=2084

用一个二维数组保存当前点往上走所能有的最大和

//c++的输入流std::cin很慢，可以使用ios::sync_with_stdio(false)加速。

#include <iostream>

#include <algorithm>
#include <cstring>
using namespace std;
int subsum[101][101];
int vex[101][101];


int main(void)

{

ios::sync_with_stdio(false);

int T, N;
cin >> T;
while (T--)
{
cin >> N;
memset(subsum, 0, sizeof(subsum));
for (int i = 1; i <= N; ++i)
{
for (int j = 1; j <= i; ++j)
{
cin >> vex[i][j];
subsum[i][j] += vex[i][j] + max(subsum[i - 1][j - 1], subsum[i - 1][j ]); 
}
}
int ans = 0;
// for (int i = 1; i <= N; ++i)
// {
// for (int j = 1; j <= N; ++j)
// cout << subsum[i][j] << ' ';
// cout << endl;
// }
for (int j = 1; j <= N; ++j)
if (subsum[N][j] > ans)
ans = subsum[N][j];
cout << ans << endl;
}
 }