第一题 DP f[i][j]表示前i个数分成j堆的最小花费，f[i][j]=min{f[k][j-1]+(将i到k+1分别移动到i的花费)}
#include<fstream>
using namespace std;
ifstream cin("leaves.in");
ofstream cout("leaves.out");
int n,k;
int i,j;
int f[1010][11];
int a[1010],sum[1010],tot[1010];
int main()
{
cin>>n>>k;
for (i=1;i<=n;i++) cin>>a[i];
for (i=1;i<=n;i++) {sum[i]=sum[i-1]+a[i];tot[i]=tot[i-1]+a[i]*(i-1);}
memset(f,63,sizeof(f));
for (i=1;i<=n;i++) f[i][1]=tot[i];
for (j=2;j<=k;j++)
for (i=j;i<=n;i++)
for (int l=j-1;l<=i-1;l++)
f[i][j]<?=f[l][j-1]+tot[i]-tot[l]-((sum[i]-sum[l])*l);
cout<<f[n][k]<<endl;
return 0;
}
#include<fstream>
using namespace std;
ifstream cin("game.in");
ofstream cout("game.out");
int n,m,tot,num1,num2;
int a[40000],b[40000],c[40000],d[40000];
int s[250][250];
void msort1(int l,int r)
{
int i,j,k,m;
if (l>=r) return;
m=(l+r)>>1;
msort1(l,m);
msort1(m+1,r);
i=l;j=m+1;k=l;
do
{
if (a[i]>a[j])
{
num1+=(m-i+1);
c[k]=a[j];
j++;k++;
}
else
{
c[k]=a[i];i++;k++;
}
}while (i<=m&&j<=r);
while (i<=m) {c[k]=a[i];k++;i++;}
while (j<=r) {c[k]=a[j];k++;j++;}
for (i=l;i<=r;i++) a[i]=c[i];
}
void msort2(int l,int r)
{
int i,j,k,m;
if (l>=r) return;
m=(l+r)>>1;
msort2(l,m);
msort2(m+1,r);
i=l;j=m+1;k=l;
do
{
if (b[i]>b[j])
{
num2+=(m-i+1);
d[k]=b[j];
j++;k++;
}
else
{
d[k]=b[i];i++;k++;
}
}while (i<=m&&j<=r);
while (i<=m) {d[k]=b[i];k++;i++;}
while (j<=r) {d[k]=b[j];k++;j++;}
for (i=l;i<=r;i++) b[i]=d[i];
}
int main()
{
int i,j;
while (cin>>n>>m)
{
num1=0;num2=0;
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
cin>>s[i][j];
tot=0;
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
{
a[++tot]=s[i][j];
}
tot=0;
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
{
b[++tot]=s[j][i];
}
msort1(1,tot);
msort2(1,tot);
if (num1==num2) {cout<<"NYY and XYY will try again"<<endl;cout<<endl;continue;}
if (m%2==1)
{
if (num1<num2) {cout<<"NYY wins the Rocket's Game"<<endl;cout<<endl;continue;}
else {cout<<"XYY wins the Rocket's Game"<<endl;cout<<endl;continue;}
}
else
{
if (num1>num2) {cout<<"NYY wins the Rocket's Game"<<endl;cout<<endl;continue;}
else {cout<<"XYY wins the Rocket's Game"<<endl;cout<<endl;continue;}
}
}
return 0;
}
#include<fstream>
using namespace std;
ifstream cin("simple.in");
ofstream cout("simple.out");
struct node
{
int x,n;
}e[200000];
int k[1000],d[1000];
int n,m,o=0,ans=0,num;
bool v[1000];
int i,j;
void add(int x,int y)
{
e[++o].x=y;
e[o].n=k[x];
k[x]=o;
}
void dfs(int x)
{
int t=k[x];
while (t)
{
if (e[t].x==i) d[i]++;
if (!v[e[t].x])
{
v[e[t].x]=true;
dfs(e[t].x);
};
t=e[t].n;
}
}
void find(int x)
{
int t=k[x];
while (t)
{
num>?=d[e[t].x];
if (!v[e[t].x])
{
v[e[t].x]=true;
find(e[t].x);
};
t=e[t].n;
}
}
int main()
{
cin>>n>>m;
int x,y;
for (i=1;i<=m;i++)
{
cin>>x>>y;
add(x,y);
add(y,x);
}
for (i=1;i<=n;i++)
{
v[i]=true;
int t=k[i];
while(t)
{
if (!v[e[t].x])
{
v[e[t].x]=true;
dfs(e[t].x);
d[i]--;
}
t=e[t].n;
}
memset(v,0,sizeof(v));
}
for (i=1;i<=n;i++)
if (!v[i])
{
num=0;
v[i]=true;
find(i);
ans+=(num<2);
}
cout<<ans<<endl;
return 0;
}
#include<fstream>
using namespace std;
ifstream cin("tele.in");
ofstream cout("tele.out");
int n,m,o;
struct node
{
int x,y,n;
}e[5000];
int k[3010];
int f[3010][3010],g[3010];
void add(int x,int y,int z)
{
e[++o].x=y;
e[o].y=z;
e[o].n=k[x];
k[x]=o;
}
int dp(int x)
{
int t,num=0;
t=k[x];
if (!t)
{
f[x][1]=g[x];
return 1;
}
while (t)
{
int p=dp(e[t].x);
num+=p;
for (int k=num;k>0;k--)
for (int j=1;j<=min(k,p);j++)
f[x][k]>?=f[x][k-j]+f[e[t].x][j]-e[t].y;
t=e[t].n;
}
return num;
}
int main()
{
int i,j,x,y;
cin>>n>>m;
for (i=1;i<=n-m;i++)
{
int t;
cin>>t;
for (j=1;j<=t;j++)
{
cin>>x>>y;
add(i,x,y);
}
}
for (i=n-m+1;i<=n;i++) cin>>g[i];
memset(f,128,sizeof(f));
for (i=1;i<=n;i++) f[i][0]=0;
j=dp(1);
int temp=m;
while (f[1][temp]<0) temp--;
cout<<temp<<endl;
return 0;
}
