Submission #36603

#	Time	Username	Problem	Language	Result	Execution time	Memory
36603		Flumen	Taxis (POI13_tak)	C++11	10 / 100	206 ms	9828 KiB

tak

#include<bits/stdc++.h>
using namespace std;
long long a[500100],v[500100];
int main(){
    int n,ans=600000,num,i,l,r,mid;
    long long m,d,tmp,tmp1,x;
    scanf("%lld%lld%d",&m,&d,&n);
    for(i=1;i<=n;i++){
        scanf("%lld",&a[i]);
        a[i]*=-1;
    }
    sort(a+1,a+n+1);
    for(i=1;i<=n;i++)a[i]*=-1;
    num=1;
    tmp=0;
    while(tmp<d){
        num++;
        tmp1=tmp;
        tmp*=2;
        tmp+=(a[num]-d);
        if(tmp<=tmp1){
            num--;
            break;
        }
    }
    //printf("%d\n",num);
    for(i=1;i<=num;i++){
        v[i]=v[i-1]*2+(a[i]-d);
        //printf("%lld\n",v[i]);
    }
    for(i=n;i>=1;i--){
        if(a[i]<m-d)continue;
        l=0;r=num;
        while(l<r){
            mid=(l+r)/2;
            //printf("%d %d\n",i,mid);
            if(i>mid){
                if(v[mid]>=d-((a[i]-m+d)/2))r=mid;
                else l=mid+1;
            }
            else{
                x=v[i-1]*(1<<(mid-i))+v[mid]-v[i]*(1<<(mid-i));
                if(x>=d-((a[i]-m+d)/2))r=mid;
                else l=mid+1;
            }
        }
        if(l<i){
            if(v[l]>=d-((a[i]-m+d)/2))ans=min(ans,l+1);
        }
        else{
            x=v[i-1]*(1<<(l-i))+v[l]-v[i]*(1<<(l-i));
            if(x>=d-((a[i]-m+d)/2))ans=min(ans,l);
        }
        //printf("%d %d\n",i,l);
    }
    if(ans==600000)ans=0;
    printf("%d",ans);
    return 0;
}

Compilation message (stderr)

tak.cpp: In function 'int main()':
tak.cpp:7:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lld%lld%d",&m,&d,&n);
                                 ^
tak.cpp:9:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld",&a[i]);
                            ^

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 10 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10