4.12头条笔试

ak了，挺简单得，许愿面试

第一题

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6+5;
int val[maxn],res[maxn],res2[maxn];
int arr[maxn];
pair<int,int>skt[maxn];
int main() {
    int t;
    cin>>t;
    while(t--){
      int n;cin>>n;
      for(int i=1;i<=n;++i)cin>>val[i];
      int top=0;
      for(int i=1;i<=n;++i){
        while(top&&skt[top].first<=val[i])--top;
        if(top){
             res[i]=i-skt[top].second-1;
        }
        else {
            res[i]=i-1;
        }
        ++top;
        skt[top]=make_pair(val[i],i);
      }
      for(int i=1;i<=n;i++)skt[i].first=skt[i].second=0;
      top=0;
      for(int i=n;i>=1;--i){
        while(top&&skt[top].first<=val[i])--top;
        if(top){
            res[i]+=skt[top].second-i-1;
        }
        else res[i]+=(n-i);
        skt[++top]=make_pair(val[i],i);
      }
      for(int i=1;i<=n;i++)cout<<res[i]<<' ';
      puts("");
    }
    return 0;
}

 

第二题

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6+5;
int val[maxn],res1[maxn],res2[maxn];
int arr[maxn];
int main() {
    int n;
    cin>>n;
    for(int i=0;i<n;++i)cin>>val[i];
    long long int ans=0;
    for(int i=n-2;i>=0;--i){
        if(val[i+1]>=val[i])continue;;
        int t = (val[i]-1)/val[i+1];
        ans+=t;
        val[i]/=(t+1);
    }
    cout<<ans;
    return 0;
}

 

第三题

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6+5;

int a[maxn],b[maxn];
int n,m;
int fin(int x){
    int l = 0,r = n+1;
    for(int i=0;i<50;++i){
        int mid=(l+r)/2;
        if(a[mid]>x)r=mid;
        else l=mid;
    }
    return l;
}
int main() {
  //  int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;++i)scanf("%d",&a[i]);
    for(int i=1;i<=m;++i)scanf("%d",&b[i]);
    sort(a+1,a+1+n);
    sort(b+1,b+1+m);
    long long int  ans(0);
    for(int i=1;i<=m;++i){
        int id = fin(b[i]);
        ans+=b[i]-a[id];
    }
    cout<<ans;
    return 0;
}

 

第四题

#include<bits/stdc++.h>
using namespace std;
const int maxn = 1e6+5;
int val[maxn],res[maxn],res2[maxn];
int arr[maxn];
pair<int,int>skt[maxn];
int main() {
    int t;
    cin>>t;
    while(t--){
      int n;cin>>n;
      for(int i=1;i<=n;++i)cin>>val[i];
      int top=0;
      for(int i=1;i<=n;++i){
        while(top&&skt[top].first<=val[i])--top;
        if(top){
             res[i]=i-skt[top].second-1;
        }
        else {
            res[i]=i-1;
        }
        ++top;
        skt[top]=make_pair(val[i],i);
      }
      for(int i=1;i<=n;i++)skt[i].first=skt[i].second=0;
      top=0;
      for(int i=n;i>=1;--i){
        while(top&&skt[top].first<=val[i])--top;
        if(top){
            res[i]+=skt[top].second-i-1;
        }
        else res[i]+=(n-i);
        skt[++top]=make_pair(val[i],i);
      }
      for(int i=1;i<=n;i++)cout<<res[i]<<' ';
      puts("");
    }
    return 0;
}