Codeforces Round #515 (Div. 3)

Codeforces Round #515 (Div. 3)

 #include<bits/stdc++.h>
 #include<iostream>
 #include<cstdio>
 #include<cstdlib>
 #include<cstring>
 #include<cmath>
 #include<algorithm>
 #include<queue>
 #include<vector>
 #include<map>
 #define lson i<<1
 #define rson i<<1|1
 #define LS l,mid,lson
 #define RS mid+1,r,rson
 #define mem(a,x) memset(a,x,sizeof(a))
 #define gcd(a,b) __gcd(a,b)
 #define ll long long
 #define ull unsigned long long
 #define lowbit(x) (x&-x)
 #define pb(x) push_back(x)
 #define enld endl
 #define mian main
 #define itn int
 #define prinft printf
 #pragma GCC optimize(2)
 //#pragma comment(linker, "/STACK:102400000,102400000")

 const double PI = acos (-1.0);
 const int INF = 0x3f3f3f3f;
 ;
 ;
 ;
 ;

 using namespace std;

 /*
 4
 10 2 3 7
 100 51 51 51
 1234 1 100 199
 1000000000 1 1 1000000000
 */
 int n,L,v,l,r;
 int main() {
     std::ios::sync_with_stdio(false);
     cin.tie(NULL);

     while(cin>>n) {
         while(n--) {
             cin>>L>>v>>l>>r;
             cout<<L/v-(r/v-(l-)/v)<<endl;
         }
     }
 }

A - Vova and Train

分区间讨论，不断更新右极值，注意边界相切的情况（1，2）（3，4）

 #include<bits/stdc++.h>
 #include<iostream>
 #include<cstdio>
 #include<cstdlib>
 #include<cstring>
 #include<cmath>
 #include<algorithm>
 #include<queue>
 #include<vector>
 #include<map>
 #define lson i<<1
 #define rson i<<1|1
 #define LS l,mid,lson
 #define RS mid+1,r,rson
 #define mem(a,x) memset(a,x,sizeof(a))
 #define gcd(a,b) __gcd(a,b)
 #define ll long long
 #define ull unsigned long long
 #define lowbit(x) (x&-x)
 #define pb(x) push_back(x)
 #define enld endl
 #define mian main
 #define itn int
 #define prinft printf
 #pragma GCC optimize(2)
 //#pragma comment(linker, "/STACK:102400000,102400000")

 const double PI = acos (-1.0);
 const int INF = 0x3f3f3f3f;
 ;
 ;
 ;
 ;

 using namespace std;

 /*
 6 2
 0 1 1 0 0 1
 */
 int n,r,a[MAXN];
 int main() {
     std::ios::sync_with_stdio(false);
     cin.tie(NULL);

     while(cin>>n>>r) {
         mem(a,);
         ;
         ;
         ; i<=n; ++i) {
             cin>>temp;
             if(temp) {
                 a[++cnt]=i;
             }
         }
         temp=;
         ;
         ;
         -)<n||a[]-r+>||a[cnt]+r-<n) cout<<-<<endl;
         else {
             ; i<=cnt; ++i) {
                 >temp+) {
                     //cout<<temp<<' '<<a[i]-r+1<<endl;
                     cout<<-<<endl;
                     flag=;
                     break;
                 }
                 if(temp>=n) {
                     //k++;
                     break;
                 }
                 <=temp+&&a[i+]-r+>temp+)||a[i]+r->=n) {
                     //cout<<i<<endl;
                     k++;
                     temp=a[i]+r-;
                 }
                 //cout<<temp<<' ';
             }
             if(!flag) cout<<k<<endl;
         }
     }
 }

B - Heaters

 #include<bits/stdc++.h>
 #include<iostream>
 #include<cstdio>
 #include<cstdlib>
 #include<cstring>
 #include<cmath>
 #include<algorithm>
 #include<queue>
 #include<vector>
 #include<map>
 #define lson i<<1
 #define rson i<<1|1
 #define LS l,mid,lson
 #define RS mid+1,r,rson
 #define mem(a,x) memset(a,x,sizeof(a))
 #define gcd(a,b) __gcd(a,b)
 #define ll long long
 #define ull unsigned long long
 #define lowbit(x) (x&-x)
 #define pb(x) push_back(x)
 #define enld endl
 #define mian main
 #define itn int
 #define prinft printf
 #pragma GCC optimize(2)
 //#pragma comment(linker, "/STACK:102400000,102400000")

 const double PI = acos (-1.0);
 const int INF = 0x3f3f3f3f;
 ;
 ;
 ;
 ;

 using namespace std;

 /*
 8
 L 1
 R 2
 R 3
 ? 2
 L 4
 ? 1
 L 5
 ? 1
 */
 int n;
 char c;
 int ind;
 int a[MAXN];
 int main() {
     //std::ios::sync_with_stdio(false);
     //cin.tie(NULL);

     while(cin>>n) {
         ,r=;
         mem(a,);
         while(n--) {
             cin>>c>>ind;
             if(c=='L') {
                 a[ind]=l--;
             } else if(c=='R') {
                 a[ind]=r++;
             } else {
                 //cout<<a[ind]<<' '<<a[l+1]<<' '<<l+1<<endl;
                 cout<<min(a[ind]-(l+),r--a[ind])<<endl;
             }
         }

     }
 }

C - Books Queries

逆推+二分

 #include<bits/stdc++.h>
 #include<iostream>
 #include<cstdio>
 #include<cstdlib>
 #include<cstring>
 #include<cmath>
 #include<algorithm>
 #include<queue>
 #include<vector>
 #include<map>
 #define lson i<<1
 #define rson i<<1|1
 #define LS l,mid,lson
 #define RS mid+1,r,rson
 #define mem(a,x) memset(a,x,sizeof(a))
 #define gcd(a,b) __gcd(a,b)
 #define ll long long
 #define ull unsigned long long
 #define lowbit(x) (x&-x)
 #define pb(x) push_back(x)
 #define enld endl
 #define mian main
 #define itn int
 #define prinft printf
 #pragma GCC optimize(2)
 //#pragma comment(linker, "/STACK:102400000,102400000")

 const double PI = acos (-1.0);
 const int INF = 0x3f3f3f3f;
 ;
 ;
 ;
 ;

 using namespace std;

 int n,m,k;
 int a[MAXN];
 int b[MAXN];

 bool check(int x) {
     mem(b,);
     ;
     ; i<=x; ++i) {
         ;
         for(int j=temp; j<=m; ++j) {
             if(b[j]+a[i]<=k) {
                 flag=;
                 b[j]+=a[i];
                 temp=j;
                 break;
             }
         }
         if(!flag)
             return false;
     }
     return true;
 }

 int main() {
     //std::ios::sync_with_stdio(false);
     //cin.tie(NULL);

     while(cin>>n>>m>>k) {
         mem(a,),mem(b,);
         ; i--)
             cin>>a[i];
         ,r=n+,mid,cnt=;
         while(cnt--) {
             mid=(l+r)/;
             if (check(mid))
                 l=mid;
             else
                 r=mid;
         }
         cout<<mid<<endl;
     }
     /*
     while(cin>>n>>m>>k) {
         for(int i=n; i>=1; i--)
             cin>>a[i];
         int x;
         cin>>x;
         cout<<check(x)<<endl;
     }
     */
 }

D - Boxes Packing