C++ :

#include <cstdio>
#include <cstring>

int n,m,q;
int a[55][55][55]={0};
 
int main()
{
    int i,j,k,l;
    
    scanf("%d%d",&n,&m);
    
    int x,y,z;
    
    memset(a,255,sizeof(a));
    
    for(i=1;i<=m;i++) 
    {
        scanf("%d%d%d",&x,&y,&z);
        if(a[x][y][1]==-1||z<a[x][y][1]) a[x][y][1]=z;
    }
    
    for(i=1;i<=n;i++) a[i][i][0]=0;
    
    for(int l=2;l<=n;l++)
    {
      	for(int k=1;k<=n;k++)
      	{
        	for(int i=1;i<=n;i++)
        	{
          		for(int j=1;j<=n;j++)
          		{ 
            		if(a[i][k][l-1]>-1&&a[k][j][1]>-1&&(a[i][j][l]==-1||a[i][j][l]>a[i][k][l-1]+a[k][j][1]))
            		{
                		a[i][j][l]=a[i][k][l-1]+a[k][j][1];
					}
				}
			}
        }
    }
    
    scanf("%d",&q);
    
    for(int i=1;i<=q;i++)
    {
        scanf("%d%d",&x,&y);
        
        double max=111111111;
        
        for(int j=0;j<=n;j++)
        {
          	if(a[x][y][j]!=-1 && a[x][y][j]<max*j)
		  	max=(double)a[x][y][j]/j;
		}
		
        if(max!=111111111)
		{
			printf("%.3f\n",max+0.000005);
		}
		else printf("OMG!\n");
    }
    
    return 0;
}

Pascal :

type
  bian=record
       y,next,len:longint;
       end;
var n,m,x,y,z,i,j,k,w,b,l:longint;
    f:array[0..50,0..50,0..50] of longint;
    ans:array[0..50,0..50] of double;
    max:double;
begin
  readln(n,m);
  fillchar(f,sizeof(f),63);
  for i:=1 to m do
  begin
    readln(x,y,z);
    if z<f[x,y,1] then f[x,y,1]:=z;
  end;
  readln(w);
  for i:=1 to n do f[i,i,0]:=0;
  for l:=2 to n do
    for k:=1 to n do
      for i:=1 to n do
        for j:=1 to n do
          if f[i,k,l-1]+f[k,j,1]<f[i,j,l] then f[i,j,l]:=f[i,k,l-1]+f[k,j,1];
  for i:=1 to n do
    for j:=1 to n do
    begin
      max:=100000;
      for l:=1 to n do if f[i,j,l]/l<max then max:=f[i,j,l]/l;
      ans[i,j]:=max;
    end;
  for i:=1 to w do
  begin
    readln(x,y);
    if ans[x,y]=100000 then writeln('OMG!');
    if ans[x,y]<>100000 then writeln(ans[x,y]:0:3);
  end;
  close(input);
  close(output);
end.