Barn Repair

链接

分析：我们不断统计相邻两个元素之间的差值，按照差值从大到小排序，在进行贪心即可

 /*
     PROB:barn1
     ID:wanghan
     LANG:C++
 */
 #include "iostream"
 #include "cstdio"
 #include "cstring"
 #include "string"
 #include "cmath"
 #include "algorithm"
 using namespace std;
 const int maxn=;
 int m,s,c;
 int stall[maxn];
 struct  Node
 {
     int sub,id;
 };
 Node p[maxn];
 bool cmp(Node x,Node y){
     return x.sub>y.sub;
 }
 int vis[maxn];
 int main()
 {
     freopen("barn1.in", "r", stdin);
     freopen("barn1.out", "w", stdout);
     cin>>m>>s>>c;
     for(int i=;i<c;i++){
         cin>>stall[i];
     }
     sort(stall,stall+c);
     for(int i=;i<c;i++){
         p[i].id=i;
         p[i].sub=stall[i]-stall[i-];
     }
     //p[c].id=c;
     //p[c].sub=s-stall[c-1];
     sort(p+,p+c,cmp);
     if(m>=c){
         cout<<c<<endl;
     }else{
         int cnt=stall[c-]-stall[];
         //cout<<cnt<<endl;
         for(int i=;i<m;i++){
             cnt-=p[i].sub;
             //cout<<"sub:"<<p[i].sub<<endl;
             //cout<<cnt<<endl;
         }
         cout<<cnt+m<<endl;
     }
 }