Dashboard - The 13th Shandong ICPC Provincial Collegiate Programming Contest - Codeforces
A.Orders
题解：
排序+遍历
代码：
#include
using namespace std;
const int N=1e5+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair pi;
const ll mod=100000007;
vectora;
int T,n,k;
ll x,y;
ll sum,res;
int tmp;
int main(){
scanf("%d",&T);
while(T--){
a.clear();
scanf("%d%d",&n,&k);
for(int i=1;i<=n;i++){
scanf("%lld%lld",&x,&y);
a.push_back({x,y});
}sort(a.begin(),a.end());
res=k;
int cnt=1,f=1;
for(int i=0;icnt){
res+=(a[i].first-cnt)*k;
cnt=a[i].first;
}//printf("i%d a[i]%d cnt%d res%lld\n",i,a[i].second,cnt,res);
if(res<0){
f=0;break;
}
}if(f)printf("Yes\n");
else printf("No\n");
}
return 0;
}
D. Fast and Fat（二分+贪心）
题解：
weight为第一关键字，speed为第二关键字排序，二分最大值，check函数判断可否满足最大值为x，遍历所有人，将速度>=x分为c组，
*二分起点 l，r 为初始最大最小值
*结束条件为 l<=r
*反向迭代器删除元素(++itc).base() 反向迭代器删除元素-CSDN博客
*看c组能否带着b组时从体重从大到小看
代码：
#include
using namespace std;
const int N=1e5+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair pi;
const int inf=1<<30;
const ll mod=100000007;
vectora,c;
vectorb;
int T,n,k;
int v,w;
int mx,mn;
int chk(int x){//最大值为x是否可行
//printf("x%d\n",x);
b.clear();c.clear();
for(int i=0;ilc)return 0;
//printf("lb%d lc%d\n",lb,lc);
auto itb=b.rbegin();
for(;itb!=b.rend();itb++){
//printf("b:%d\n",*itb);
int flag=0;
for(auto itc=c.rbegin();itc!=c.rend();itc++){
//printf("cw:%d cs:%d %d\n",itc->first,itc->second,itc->second+itc->first-*itb);
if((itc->second+itc->first-*itb)>=x){
c.erase((++itc).base());
flag=1;
break;
}
}if(flag==0)return 0;
}return 1;
}
int main(){
scanf("%d",&T);
while(T--){
mx=0,mn=inf;
a.clear();
scanf("%d",&n);
for(int i=1;i<=n;i++){
scanf("%d%d",&v,&w);
a.push_back({w,v});
mx=max(mx,v);
mn=min(mn,v);
}sort(a.begin(),a.end());//按weight，speed升序排序
int l=mn,r=mx,res=mn;
while(l<=r){
int mid=(l+r)/2;
if(chk(mid))l=mid+1,res=mid;
else r=mid-1;
}printf("%d\n",res);
}
return 0;
}
G. Matching
*等式变换
*求取最大值时考虑负数
*考虑是否有孤立点
#include
using namespace std;
const int N=1e5+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair pi;
const int inf=1<<30;
const ll mod=1e9+7;
int T,n,x;
ll res;
/*
ai-i=aj-j
>
*/
unordered_map>mp;
int main(){
scanf("%d",&T);
while(T--){
res=0;
scanf("%d",&n);
mp.clear();
for(int i=1;i<=n;i++){
scanf("%d",&x);
mp[x-i].push_back(x);
}for(auto i:mp){
vectora=i.second;
sort(a.begin(),a.end());
for(int j=a.size()-1;j>=1;j-=2){
if((a[j]+a[j-1])>0)res+=a[j]+a[j-1];
else break;
}
}printf("%lld\n",res);
}
return 0;
}
I.Three Dices
#include
using namespace std;
const int N=1e5+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair pi;
const int inf=1<<30;
const ll mod=100000007;
int a,b;
int chk(int a,int b){
if(a>12||b>18)return 0;
/*
4+4+4=12
4+4+1=9
4+1+1=6
1+1+1=3
4+4=8
4+1=5
1+1=2
4
1
*/
if(a!=0&&a%3==0&&b==0)return 1;
if((a==8||a==5||a==2)&&(b==2||b==3||b==5||b==6))return 1;
/*
6+6=12
6+5=11
6+3=9
6+2=8
5+5=10
5+3=8
5+2=7
3+3=6
3+2=5
2+2=4
4<=b<=12
*/
if(a==4&&(4<=b&&b<=12))return 1;
if(a==1&&(4<=b&&b<=12))return 1;
/*
6+6+6=18
6+6+5=17
6+6+3=15
6+6+2=14
6+5+5=16
6+5+3=14
6+5+2=13
6+3+3=12
6+3+2=11
6+2+2=10
5+5+5=15
5+5+3=13
5+5+2=12
5+3+3=11
5+3+2=10
5+2+2=9
3+3+3=9
3+3+2=8
3+2+2=7
2+2+2=6
6<=b<=18
*/
if(a==0&&(6<=b&&b<=18))return 1;
return 0;
}
int main(){
scanf("%d%d",&a,&b);
if(chk(a,b))printf("Yes");
else printf("No");
return 0;
}
