poj1163 - DP遞推、遞歸寫法
阿新 • • 發佈：2017-08-23
end calculate base main blog can idt integer field 本題超鏈接：http://poj.org/problem?id=1163
The Triangle
Figure 1 shows a number triangle. Write a program that calculates the highest sum of numbers passed on a route that starts at the top and ends somewhere on the base. Each step can go either diagonally down to the left or diagonally down to the right.
| Time Limit: 1000MS | Memory Limit: 10000K | |
| Total Submissions: 50977 | Accepted: 30888 |
Description
7
3 8
8 1 0
2 7 4 4
4 5 2 6 5
(Figure 1)
Input
Your program is to read from standard input. The first line contains one integer N: the number of rows in the triangle. The following N lines describe the data of the triangle. The number of rows in the triangle is > 1 but <= 100. The numbers in the triangle, all integers, are between 0 and 99.Output
Sample Input
5 7 3 8 8 1 0 2 7 4 4 4 5 2 6 5
Sample Output
30
Source
IOI 1994 DP的遞推寫法1 #include <cstdio> 2 #include <cstring> 3 #include <cmath> 4 #include <iostream> 5 using namespacestd; 6 7 int dp[105][105]; 8 int f[105][105]; 9 10 int func(int n) 11 { 12 for(int i=n-1;i>=1;i--) 13 { 14 for(int j=1;j<=i;j++) 15 { 16 dp[i][j]=max(dp[i+1][j],dp[i+1][j+1])+f[i][j]; 17 } 18 } 19 return dp[1][1]; 20 } 21 int main() 22 { 23 int n; 24 while(~scanf("%d",&n)) 25 { 26 for(int i=1;i<=n;i++) 27 { 28 for(int j=1;j<=i;j++) 29 { 30 scanf("%d",&f[i][j]); 31 } 32 } 33 for(int i=1;i<=n;i++) dp[n][i]=f[n][i]; 34 printf("%d\n",func(n)); 35 } 36 37 return 0; 38 }
DP的遞歸寫法
1 #include <cstdio> 2 #include <cstring> 3 #include <cmath> 4 #include <iostream> 5 using namespace std; 6 7 int dp[105][105]; 8 int f[105][105]; 9 int n; 10 11 int func(int i,int j) 12 { 13 if(i==n) return dp[i][j]=f[i][j]; 14 if(dp[i][j]!=-1) return dp[i][j]; 15 return dp[i][j]=max(func(i+1,j),func(i+1,j+1))+f[i][j]; 16 17 } 18 int main() 19 { 20 21 while(~scanf("%d",&n)) 22 { 23 memset(dp,-1,sizeof(dp)); 24 for(int i=1;i<=n;i++) 25 { 26 for(int j=1;j<=i;j++) 27 { 28 scanf("%d",&f[i][j]); 29 } 30 } 31 32 printf("%d\n",func(1,1)); 33 } 34 35 return 0; 36 }
poj1163 - DP遞推、遞歸寫法