自认思路清晰，方法正确了！

后4个测试数据两个输出0，两个比标准答案长，麻烦帮忙看看大牛！

program P1139;

var i,j,n,m:longint;

a,x,y:array[0..101,0..501] of longint;

f:array[0..101,0..501] of int64;

b:array[0..50000] of longint;

procedure work;

var i,j:longint;

begin

for i:=2 to m do

begin

for j:=1 to n do

begin

f:=f+a;

x:=i-1;

y:=j;

end;

for j:=2 to n do

if f>f+a then

begin

f:=f+a;

x:=i;

y:=j-1;

end;

for j:=n-1 downto 1 do

if f>f+a then

begin

f:=f+a;

x:=i;

y:=j+1;

end;

end;

end;

procedure print;

var x1,y1,i,j,k:longint;

min:int64;

begin

min:=1000000000;

for j:=1 to n do

if f[m,j]