RT，dp 50分，不知道错哪了

#include <iostream>

using namespace std;

int n, m, a[110][110], dp[110][110];

int main() {
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
	for (int j = 1; j <= m; j++) {
	  cin >> a[i][j];
	}
  }
  dp[1][1] = a[1][1];
  for (int j = 2; j <= m; j++) {
	for (int i = 1; i <= n; i++) {
	  dp[i][j] = max(dp[i - 1][j - 1], max(dp[i][j - 1], dp[i + 1][j - 1])) + a[i][j];
	}
  }
  cout << dp[n][m];
  return 0;
}