Init

ACMOJ-1669.cpp

@@ -0,0 +1,61 @@
+#include<iostream>
+#include<cstring>
+#include<algorithm>
+using namespace std;
+const int inf=0x3f3f3f3f;
+const int maxmn=505;
+int n,m,d[maxmn],position[maxmn];
+int dp[maxmn][maxmn],pre[maxmn][maxmn],suf[maxmn][maxmn];
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d%d",&n,&m);
+    for(int i=1;i<=n-1;i++)
+        scanf("%d",&d[i]);
+    for(int i=2;i<=n;i++)
+        position[i]=position[i-1]+d[i-1];
+    memset(dp,0x3f,sizeof(dp));
+    for(int i=1;i<=n;i++)
+    {
+        dp[i][1]=0;
+        for(int j=i-1;j>=1;j--)
+            dp[i][1]+=position[i]-position[j];
+        for(int j=i+1;j<=n;j++)
+            dp[i][1]+=position[j]-position[i];
+    }
+    for(int i=1;i<=n;i++)
+    {
+        for(int j=i+1;j<=n;j++)
+        {
+            pre[i][j]=pre[i][j-1]+position[j]-position[i];
+        }
+    }
+    for(int i=n;i>=1;i--)
+    {
+        for(int j=i-1;j>=1;j--)
+        {
+            suf[i][j]=suf[i][j+1]+position[i]-position[j];
+        }
+    }
+    for(int i=2;i<=n;i++)
+        for(int j=2;j<=m;j++)
+        {
+            int p=i;
+            for(int k=i-1;k>=1;k--)
+            {
+                while(p-1>=1&&position[i]-position[p-1]<position[p-1]-position[k])
+                    p--;
+                dp[i][j]=min(dp[i][j],
+                    dp[k][j-1]
+                    -(n-i+1)*(position[i]-position[k])
+                    -pre[k][i-1]+pre[k][p-1]+suf[i][p]
+                    );
+            }
+        }
+    int res=inf;
+    for(int i=1;i<=n;i++) res=min(res,dp[i][m]);
+    printf("%d\n",res);
+	return 0;
+}