poj-3176 Cow Bowling &&poj-1163 The Triangle && hihocoder #1037 : 数字三角形 （基础dp）

经典的数塔模型。

动态转移方程：  dp[i][j]=max(dp[i+1][j],dp[i+1][j+1])+p[i][j];

 #include <iostream>
 #include <cstdio>
 #include <cmath>
 #include <vector>
 #include <cstring>
 #include <string>
 #include <algorithm>
 #include <string>
 #include <set>
 #include <functional>
 #include <numeric>
 #include <sstream>
 #include <stack>
 #include <map>
 #include <queue>
 #pragma comment(linker, "/STACK:102400000,102400000")
 #define CL(arr, val)    memset(arr, val, sizeof(arr))

 #define ll long long
 #define inf 0x7f7f7f7f
 #define lc l,m,rt<<1
 #define rc m + 1,r,rt<<1|1
 #define pi acos(-1.0)

 #define L(x)    (x) << 1
 #define R(x)    (x) << 1 | 1
 #define MID(l, r)   (l + r) >> 1
 #define Min(x, y)   (x) < (y) ? (x) : (y)
 #define Max(x, y)   (x) < (y) ? (y) : (x)
 #define E(x)        (1 << (x))
 #define iabs(x)     (x) < 0 ? -(x) : (x)
 #define OUT(x)  printf("%I64d\n", x)
 #define lowbit(x)   (x)&(-x)
 #define Read()  freopen("a.txt", "r", stdin)
 #define Write() freopen("b.txt", "w", stdout);
 #define maxn 1000000000
 #define N 500
 using namespace std;

 int dp[N][N];
 int main()
 {
     int n;
     scanf("%d",&n);
     for(int i=;i<n;i++)
         for(int j=;j<=i;j++) scanf("%d",&dp[i][j]);
     for(int i=n-;i>=;i--)
         for(int j=;j<=i;j++)
         dp[i][j]=dp[i][j]+max(dp[i+][j],dp[i+][j+]);
     printf("%d\n",dp[][]);
     return ;
 }

只用一维数组。注意  保证下一层的数由上一层推出，不受同一层的干扰。

 #include <iostream>
 #include <cstdio>
 #include <cmath>
 #include <vector>
 #include <cstring>
 #include <string>
 #include <algorithm>
 #include <string>
 #include <set>
 #include <functional>
 #include <numeric>
 #include <sstream>
 #include <stack>
 #include <map>
 #include <queue>
 #pragma comment(linker, "/STACK:102400000,102400000")
 #define CL(arr, val)    memset(arr, val, sizeof(arr))

 #define ll long long
 #define inf 0x7f7f7f7f
 #define lc l,m,rt<<1
 #define rc m + 1,r,rt<<1|1
 #define pi acos(-1.0)

 #define L(x)    (x) << 1
 #define R(x)    (x) << 1 | 1
 #define MID(l, r)   (l + r) >> 1
 #define Min(x, y)   (x) < (y) ? (x) : (y)
 #define Max(x, y)   (x) < (y) ? (y) : (x)
 #define E(x)        (1 << (x))
 #define iabs(x)     (x) < 0 ? -(x) : (x)
 #define OUT(x)  printf("%I64d\n", x)
 #define lowbit(x)   (x)&(-x)
 #define Read()  freopen("a.txt", "r", stdin)
 #define Write() freopen("b.txt", "w", stdout);
 #define maxn 1000000000
 #define N 500
 using namespace std;

 int dp[N];
 int main()
 {
     //Read();
     int n,a,r=;
     scanf("%d",&n);
     for(int i=;i<=n;i++)
     {
         for(int j=i;j>=;j--)
         {
             scanf("%d",&a);
             dp[j]=max(dp[j],dp[j-])+a;
             r=max(r,dp[j]);
             //printf("%d ",dp[j]);
         }
        //printf("\n");
     }
     printf("%d\n",r);
     return ;
 }