C++ :

#include<iostream>
#include<cstdlib>
#include<cstdio>
using namespace std;
double f[1001];
long long len,wei,n,w[1001],v[1001],sum[1001],vmin[1001][1001];
int main ()
{
    scanf ("%I64d%I64d%I64d",&wei,&len,&n);
    for (int b=1;b<=n;++b){scanf ("%I64d%I64d",&w[b],&v[b]);sum[b]=sum[b-1]+w[b];vmin[b][b]=v[b];}
    for (int b=1;b<n;++b)for (int c=b+1;c<=n;++c)vmin[b][c]=min(v[c],vmin[b][c-1]);
    for (int i=1;i<=n;++i)
    {
        f[i]=(double)len/v[i]+f[i-1];
        for (int j=i-1;j>=1;--j)
            if (sum[i]-sum[j-1]<=wei)f[i]=min(f[i],f[j-1]+(double)len/vmin[j][i]);
            else break;
    }
    printf ("%.1lf",f[n]*60);
    return 0;
}

Pascal :

var
max,len,n:int64;
i,j:longint;
w,v,f:array[0..1000]of extended;
minv,t:extended;
begin   
read(max,len,n);  
for i:=1 to n do  
read(w[i],v[i]);  
f[0]:=0;   
f[1]:=len/v[1]; 
for i:=2 to n do     
begin           
f[i]:=1e24;        
minv:=1e24;         
t:=0;          
for j:=i downto 1 do  
begin                  
t:=t+w[j];              
if v[j]<minv then minv:=v[j]; 
if t>max then break;              
if minv<>0 then if f[j-1]+len/minv<f[i] then f[i]:=f[j-1]+len/minv;       
end;    
end;  
writeln(f[n]*60:0:1);   
end.