Back file | Check number of squares

Title Description Description
with N*n (n<=9), we fill some of these squares with positive integers, while the other squares
Person number 0. As shown (see examples):
A
0 0 0 0 0 0 0 0
0 0 0 0 6 0 0
0 0 0 0 7 0 0 0
0 0 0 0 0 0 0
0 0 0 0 4 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
B
someone from a point in the upper left corner of the picture, you can walk down, or to the right, until you reach the lower right corner of B
Point. On the way, he can take the number in the squares (the squares will change to the number 0).
this person from point A to point B to walk two times, try to find out 2 such paths, so that the sum of the obtained number is the largest.

input/output format Input/output
Input Format:
the first behavior of the input is an integer n (a square chart representing n*n), followed by three integers per line, the first two
represents the position, and the third number is the number placed at that position. A single line of 0 indicates the end of the input.
output Format:
just output An integer that represents the maximum and the 2 paths that are obtained.
 
Input Sample:
8
2 3
2 6 6
3 5 7
4 4
5 2
5 6 4
6 3
7 2
0 0 0
Output Sample:

Interpretation of the topic: The key to this problem is the determination of the two-time path. It is undoubtedly the best choice not to change the coordinates of the map. So we only need to search the optimal path, then use dynamic programming to find the shortest path from the remaining lattice. (Worship Myf, this question can also use four-dimensional move to return but really do not want to write ... ）

varN,i,j,answer,t,k:longint; A,map,p:Array[0.. One,0.. One] ofLongint;functionMax (a,b:longint): Longint;begin   ifA>b Thenexit (a); Exit (b); End;
procedureWork (x,y,ans:longint);begin   if(x<1)or(y<1)or(x>n)or(y>n) Thenexit; if(x=n) and(y=n) Then     beginP[n,n]:=0; ans:=ans+Map[x,y];  fori:=1  toN Do          forj:=1  toN DoA[i,j]:=map[i,j]*P[i,j];  fori:=1  toN Do          forj:=1  toN DoA[i,j]:=a[i,j]+max (a[i-1, j],a[i,j-1]); Answer:=max (answer,a[n,n]+ans); End; P[x,y]:=0; Work (x, Y+1, ans+Map[x,y]); Work (x+1, y,ans+Map[x,y]); P[x,y]:=1; End;
beginREADLN (n);  fori:=1  toN Do      forj:=1  toN Dop[i,j]:=1;  whileTrue Do     beginreadln (i,j,k); ifI=0  ThenBreak ; MAP[I,J]:=K; End; Answer:=0; Work (1,1,0); Writeln (answer); End. 

Back file | Check number of squares