E 凸多边形的划分
https://ac.nowcoder.com/acm/contest/5902/E
区间DP+高精度
给出一份__int128的代码和java的代码
1 #include<bits/stdc++.h> 2 using namespace std; 3 const int maxn=55; 4 inline void read(__int128 &X) 5 { 6 X = 0; 7 int w=0; char ch=0; 8 while(!isdigit(ch)) {w|=ch=='-';ch=getchar();} 9 while(isdigit(ch)) X=(X<<3)+(X<<1)+(ch^48),ch=getchar(); 10 if (w) X = -X; 11 } 12 inline void print(__int128 x) 13 { 14 if (!x) return ; 15 if (x < 0) putchar('-'),x = -x; 16 print(x / 10); 17 putchar(x % 10 + '0'); 18 } 19 __int128 dp[maxn][maxn]; int a[maxn]; 20 const __int128 INF=1e30; 21 int main(void) 22 { 23 int n; scanf("%d",&n); 24 for(int i=1;i<=n;i++) scanf("%d",&a[i]); 25 for(int len=3;len<=n;len++) 26 { 27 for(int i=1;i+len-1<=n;i++) 28 { 29 int j=i+len-1; 30 dp[i][j]=INF; 31 for(int k=i+1;k<=j-1;k++) 32 { 33 dp[i][j]=min(dp[i][j],dp[i][k]+dp[k][j]+(__int128)a[i]*a[j]*a[k]); 34 } 35 } 36 } 37 print(dp[1][n]); printf("\n"); 38 return 0; 39 }
1 import java.math.BigInteger; 2 import java.util.Scanner; 3 public class Main{ 4 public static void main(String[] args) { 5 Scanner cin=new Scanner(System.in); 6 while(cin.hasNext()){ 7 int n=cin.nextInt(); 8 BigInteger []a= new BigInteger[n+10]; 9 BigInteger[][]dp= new BigInteger[100][100]; 10 for(int i=1;i<=n;i++){ 11 a[i]=cin.nextBigInteger(); 12 } 13 for(int i=0;i<100;i++){ 14 for(int j=0;j<100;j++){ 15 dp[i][j]=new BigInteger("134567456745674567567567567134567456745674567567567567"); 16 } 17 } 18 for(int i=n;i>=1;i--){ 19 for(int j=i+1;j<=n;j++){ 20 if(j-i==1){ 21 dp[i][j]=BigInteger.ZERO; 22 } 23 else if(j-i==2){ 24 dp[i][j]=a[i].multiply(a[i+1].multiply(a[i+2])); 25 }else{ 26 for(int k=i+1;k<=j-1;k++){ 27 BigInteger pre=dp[i][k].add(dp[k][j].add(a[i].multiply(a[j].multiply(a[k])))); 28 if(dp[i][j].compareTo(pre)==1){ 29 dp[i][j]=pre; 30 } 31 } 32 } 33 } 34 } 35 System.out.println(dp[1][n]); 36 } 37 } 38 }
