hdu 5491(2015合肥网赛)The Next

题目;http://acm.hdu.edu.cn/showproblem.php?pid=5491

题意就是,T组测试数据。然后L，S1，S2。L的二进制中有x个1，x满足  S1<=x<=S2

求满足S1<=x<=S2

直接暴力,但是有个地方要注意,当L在递增枚举的过程中,X小于S1的时候,将其二进制中S1-X个0位转化成1,不然会超时

 #include<cstdio>
 using namespace std;
 typedef long long ll;
 int main()
 {
     ll t,ans=,a[],n,s1,s2;
     ll i,sum;
     scanf("%I64d",&t);
     while (t--)
     {
         scanf("%I64d %I64d %I64d",&n,&s1,&s2);
         int flag=;
         while ()
         {
             n++;
             ll e=n;
             i=,sum=;
             while (e)
             {
                 a[++i]=e%;
                 if (e%) sum++;
                 e/=;
             }
             if (sum<s1)
             {
                 ll q=s1-sum,j,w=;
                 for (j=;j<=i;j++)
                 {
                     if (!a[j])
                     {
                         a[j]=;
                         w++;
                     }
                     if (w==q) break;
                 }
                 break;
             }
             if (sum<=s2&&sum>=s1)
             {
                 flag=;
                 break;
             }
         }
         printf("Case #%I64d: ",ans++);
         if (flag==) printf("%I64d\n",n);
         else
         {
             sum=;ll x=;
             for (ll j=;j<=i;j++)
             {
                 sum+=x*a[j];
                 x*=;
             }
             printf("%I64d\n",sum);
         }
     }
     return ;
 }