delete pics to save space

1.1220.cpp

@@ -0,0 +1,29 @@
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+using namespace std;
+typedef long long LL;
+const int maxn=55;
+int n,c,p[maxn],w[maxn];
+LL s[maxn],f[maxn][maxn][2];
+int main()
+{
+	#ifdef local
+	freopen("pro.in","r",stdin);
+	#endif
+	scanf("%d%d",&n,&c);
+	for(int i=1;i<=n;i++) scanf("%d%d",&p[i],&w[i]);
+	for(int i=1;i<=n;i++) s[i]=s[i-1]+w[i];
+	memset(f,0x3f,sizeof(f));
+	f[c][c][0]=f[c][c][1]=0;
+	for(int len=1;len<n;len++)
+		for(int i=1;i+len-1<=n;i++)
+		{
+			int j=i+len-1;
+			LL W=s[i-1]+s[n]-s[j];
+			if(i>1) f[i-1][j][0]=min(f[i-1][j][0],min(f[i][j][0]+(p[i]-p[i-1])*W,f[i][j][1]+(p[j]-p[i-1])*W));
+			if(j<n) f[i][j+1][1]=min(f[i][j+1][1],min(f[i][j][0]+(p[j+1]-p[i])*W,f[i][j][1]+(p[j+1]-p[j])*W));
+		}
+	printf("%lld\n",min(f[1][n][0],f[1][n][1]));
+	return 0;
+}