最短路spfa dijkstra模板

spfa

var
    a,b:array[1..5000,0..5000] of longint;
    d,f:array[1..100000] of longint;
    bz:array[1..10000] of boolean;
    i,j,k,l,x,y,z,n,m,s,t:longint;
begin
    read(n,m,s,t);
    fillchar(b,sizeof(b),0);
    fillchar(d,sizeof(d),0);
    fillchar(bz,sizeof(bz),false);
    for i:=1 to m do
    begin
        read(x,y,z);
        inc(b[x,0]);
        b[x,b[x,0]]:=y;
        a[x,y]:=z;
        inc(b[y,0]);
        b[y,b[y,0]]:=x;
        a[y,x]:=z;
    end;
    i:=0;
    j:=1;
    d[1]:=s;
    fillchar(f,sizeof(f),127);
    f[s]:=0;
    bz[s]:=true;
    while i<j do
    begin
        inc(i);
        k:=d[i];
        for l:=1 to b[k,0] do
        begin
            if f[b[k,l]]>f[k]+a[k,b[k,l]] then
            begin
                f[b[k,l]]:=f[k]+a[k,b[k,l]];
                if bz[b[k,l]]=false then
                begin
                    bz[b[k,l]]:=true;
                    inc(j);
                    d[j]:=b[k,l];
                end;
            end;
        end;
        bz[k]:=false;
    end;
    writeln(f[t]);
end.

dij没有堆优化

var
    a:array[1..5000,1..5000] of longint;
    b:array[1..5000,0..5000] of longint;
    bz:array[1..5000] of boolean;
    f:array[1..5000] of longint;
    i,x,n,m,s,t,y,z,min:longint;
begin
    assign(input,'dij.in'); reset(input);
    assign(output,'dij.out'); rewrite(output);
    read(n,m,s,t);
    fillchar(b,sizeof(b),0);
    for i:=1 to m do
    begin
        read(x,y,z);
        a[x,y]:=z;
        a[y,x]:=z;
        inc(b[x,0]);
        inc(b[y,0]);
        b[x,b[x,0]]:=y;
        b[y,b[y,0]]:=x;
    end;

    fillchar(f,sizeof(f),127);
    fillchar(bz,sizeof(bz),false);
    f[s]:=0;
    x:=s;
    repeat
        bz[x]:=true;
        for i:=1 to b[x,0] do
        begin
            if (a[x,b[x,i]]>0)and(bz[b[x,i]]=false)and(f[x]+a[x,b[x,i]]<f[i]) then
            f[b[x,i]]:=a[x,b[x,i]]+f[x];
        end;
        min:=maxlongint;
        for i:=1 to n do
        begin
            if (bz[i]=false)and(f[i]<min) then begin min:=f[i]; x:=i; end;
        end;
    until min=maxlongint;

    writeln(f[t]);
    close(input); close(output);
end.

一般情况下，spfa用的多一点。好打容易理解而且一般能过。
spfa题目：
IOIOI卡片占卜
NOIP2013提高组 华容道
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