CONTEST45 呵呵呵呵呵

题目质量差评！为什么不给数据范围!

A.乘积最大3

题目：http://dev.luogu.org/problem/show?pid=2172

题解：sb题，均值定理。

代码：

 #include<cstdio>
 #include<cstdlib>
 #include<cmath>
 #include<cstring>
 #include<algorithm>
 #include<iostream>
 #include<vector>
 #include<map>
 #include<set>
 #include<queue>
 #include<string>
 #define inf 1000000000
 #define maxn 10000000
 #define maxm 500+100
 #define eps 1e-10
 #define ll long long
 #define pa pair<int,int>
 #define for0(i,n) for(int i=0;i<=(n);i++)
 #define for1(i,n) for(int i=1;i<=(n);i++)
 #define for2(i,x,y) for(int i=(x);i<=(y);i++)
 #define for3(i,x,y) for(int i=(x);i>=(y);i--)
 #define mod 1000000007
 using namespace std;
 inline ll read()
 {
     ll x=,f=;char ch=getchar();
     while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}
     while(ch>=''&&ch<=''){x=*x+ch-'';ch=getchar();}
     return x*f;
 }
 ll n,m,tmp,a[maxn];
 int main()
 {
     freopen("input.txt","r",stdin);
     freopen("output.txt","w",stdout);
     n=read();m=read();
     for1(i,m)a[i]=n/m;
     tmp=n-(n/m)*m;
     for3(i,m,m-tmp+)a[i]++;
     for1(i,m-)printf("%lld ",a[i]);
     printf("%lld\n",a[m]);
     return ;
 }

B.刮油漆

题目：http://dev.luogu.org/problem/show?pid=U155

题解：先差分算出每个点的高度，然后单调栈搞掉。

不知道哪写残了一直WA，没AK真不爽。。。

代码：

 #include<cstdio>
 #include<cstdlib>
 #include<cmath>
 #include<cstring>
 #include<algorithm>
 #include<iostream>
 #include<vector>
 #include<map>
 #include<set>
 #include<queue>
 #include<string>
 #define inf 1000000000
 #define maxn 1000000+1000
 #define maxm 500+100
 #define eps 1e-10
 #define ll long long
 #define pa pair<int,int>
 #define for0(i,n) for(int i=0;i<=(n);i++)
 #define for1(i,n) for(int i=1;i<=(n);i++)
 #define for2(i,x,y) for(int i=(x);i<=(y);i++)
 #define for3(i,x,y) for(int i=(x);i>=(y);i--)
 #define mod 1000000007
 using namespace std;
 inline int read()
 {
     int x=,f=;char ch=getchar();
     while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}
     while(ch>=''&&ch<=''){x=*x+ch-'';ch=getchar();}
     return x*f;
 }
 int n,ans,mx,top,a[maxn],b[maxn],sta[maxn];
 int main()
 {
     freopen("input.txt","r",stdin);
     freopen("output.txt","w",stdout);
     n=read();
     for1(i,n)
      {
       int x=read(),y=read();
       a[x]++,a[y+]--;
       if(y+>mx)mx=y+;
      }
     for1(i,mx)b[i]=b[i-]+a[i];
     ans=mx;
     sta[top=]=;
     for1(i,mx)
     {
         while(top>&&sta[top]>b[i])top--;
         if(sta[top]==b[i])ans--;else sta[++top]=b[i];
     }
     printf("%d\n",ans);
     return ;
 }

C.选学霸

题目：http://dev.luogu.org/problem/show?pid=2170

题解：并查集完了之后背包，怎么昨天一天做了两道这种题？

代码：

 #include<cstdio>
 #include<cstdlib>
 #include<cmath>
 #include<cstring>
 #include<algorithm>
 #include<iostream>
 #include<vector>
 #include<map>
 #include<set>
 #include<queue>
 #include<string>
 #define inf 1000000000
 #define maxn 1000000+1000
 #define maxm 500+100
 #define eps 1e-10
 #define ll long long
 #define pa pair<int,int>
 #define for0(i,n) for(int i=0;i<=(n);i++)
 #define for1(i,n) for(int i=1;i<=(n);i++)
 #define for2(i,x,y) for(int i=(x);i<=(y);i++)
 #define for3(i,x,y) for(int i=(x);i>=(y);i--)
 #define mod 1000000007
 using namespace std;
 inline int read()
 {
     int x=,f=;char ch=getchar();
     while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}
     while(ch>=''&&ch<=''){x=*x+ch-'';ch=getchar();}
     return x*f;
 }
 int n,m,k,ans,tot,sum,fa[maxn],a[maxn],s[maxn];
 bool f[maxn];
 inline int find(int x){return fa[x]==x?x:fa[x]=find(fa[x]);}
 int main()
 {
     freopen("input.txt","r",stdin);
     freopen("output.txt","w",stdout);
     n=read();k=read();m=read();
     for1(i,n)fa[i]=i;
     for1(i,m)
     {
         int x=find(read()),y=find(read());
         if(x!=y)fa[x]=y;
     }
     for1(i,n)s[find(i)]++;
     for1(i,n)if(s[i])a[++tot]=s[i];
     f[]=;
     for1(i,tot)
     {
      for3(j,sum,)
       if(f[j])f[j+a[i]]=;
      sum+=a[i];
     }
     for3(i,k,)if(f[i]){ans=i;break;}
     for2(i,k,n)if(f[i]){if(abs(i-k)<k-ans)ans=i;break;}
     printf("%d\n",ans);
     return ;
 }

这场比赛没有好好做，因为看起来都是些sb题。。。