include [HTML_REMOVED]
include [HTML_REMOVED]
include [HTML_REMOVED]
using namespace std;
int f[1010][1010], v[1010][1010];
int n;
int dp(int i, int j) {
int &ans = f[i][j];
if(ans) return ans;
if(i == n - 1) {
ans = v[i][j];
return ans;
}
ans = max(dp(i + 1, j + 1) + v[i][j], dp(i + 1, j) + v[i][j]);
return ans;
}
int main(void) {
scanf(“%d”, &n);
for(int i = 0; i < n; i ) {
for(int j = 0; j <= i; j ) {
scanf(“%d”, &v[i][j]);
}
}
// memset(f, -1, sizeof f);
printf("%d", dp(0, 0));
return 0;
}