#include<stdio.h>
#define inf 2000000000
int main()
{
    long d[1001],s[1001],i,mint,m,t,x,a[1001],sum;
    while(scanf("%ld %ld",&t,&x)!=EOF)
    {
        scanf("%ld",&m);
        for(i=0;i<m;i++)
        {
            scanf("%ld %ld",d+i,s+i);
            if(d[i]%s[i]!=0)
                a[i]=d[i]/s[i]+1;
            else
                a[i]=d[i]/s[i];
        }
        mint=inf;
        for(i=0;i<m;i++)
        {
            if(mint>a[i])
                mint=a[i];
        }
        if(mint>t)
        {
            sum=t*x;
            printf("%ld\n",sum);
            continue;
        }
        sum=(mint-1)*x;
        t=t-mint+1;
        sum+=t/2*x;
        printf("%ld\n",sum);
    }
    return 0;
}

• try this (25) Crying 2005-10-16 19:43:13
  • 3Q (0) cqxhh 2005-10-16 19:52:47
  • 膜拜 (0) hanlonglonglong 2014-09-16 09:41:47