2.装进肚子

https://ac.nowcoder.com/acm/contest/19850/B

#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
typedef struct node{
    int a;
    int b;
}NUM;
bool cmp(NUM t,NUM y){
    return t.a-t.b>y.a-y.b;
}
int main(){
    NUM p[100005];
    int n,k;
    long long ans=0;
    cin>>n>>k;
    for(int i=0;i<n;i++){
        cin>>p[i].a;
    }
    for(int i=0;i<n;i++){
        cin>>p[i].b;
    }
    sort(p,p+n,cmp);
    for(int i=0;i<k;i++){
        ans+=p[i].a;
    }
    for(int i=k;i<n;i++){
        ans+=p[i].b;
    }
    cout<<ans<<endl;
    return 0;
}

3.  牛牛的三角形

https://ac.nowcoder.com/acm/contest/19850/C

#include<bits/stdc++.h>
using namespace std;
int main(){
    int n,flag=0;
    cin>>n;
    vector<int> a;
    for(int i=0;i<n;i++){
        int e;
        cin>>e;
        a.push_back(e);
    }
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
            for(int k=0;k<n;k++){
                if(i!=j&&j!=k&&k!=i){
                    if(a[i]+a[j]>a[k]&&abs(a[i]-a[j])<a[k]){
                        flag=1;
                        cout<<a[i]<<" "<<a[j]<<" "<<a[k]<<endl;
                        break;
                    }
                }
            }
            if(flag) break;
        }
        if(flag) break;
    }
    if(!flag) cout<<"No solution\n";
    return 0;
}

4.[NOIP1998]拼数

https://ac.nowcoder.com/acm/contest/19850/D

#include<bits/stdc++.h>
using namespace std;
bool cmp(string a,string b){
    return a+b>b+a;
}
int main(){
    string s[25];
    int n;
    cin>>n;
    for(int i=0;i<n;i++){
        cin>>s[i];
    }
    sort(s,s+n,cmp);
    for(int i=0;i<n;i++){
        cout<<s[i];
    }
    cout<<endl;
    return 0;
}

5.