简单题

#include

<

iostream

>

#include

<

cstdio

>

#include

<

cstdlib

>

#include

<

cstring

>

using

namespace

std;

#define

maxn 400

int

n, ball[maxn][maxn], f[maxn][maxn];

int

main()

{

//

freopen("t.txt", "r", stdin);

scanf(

"

%d

"

,

&

n);

for

(

int

i

=

1

; i

<=

n; i

++

)

for

(

int

j

=

1

; j

<=

i; j

++

)

scanf(

"

%d

"

,

&

ball[i][j]);

for

(

int

i

=

1

; i

<=

n; i

++

)

for

(

int

j

=

1

; j

<=

i; j

++

)

f[i][j]

=

ball[i][j]

+

max(f[i

-

1

][j

-

1

], f[i

-

1

][j]);

int

ans

=

0

;

for

(

int

i

=

1

; i

<=

n; i

++

)

ans

=

max(ans, f[n][i]);

printf(

"

%d\n

"

, ans);

return

0

;

}