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];
1 #include <iostream> 2 #include <cstdio> 3 #include <cmath> 4 #include <vector> 5 #include <cstring> 6 #include <string> 7 #include <algorithm> 8 #include <string> 9 #include <set> 10 #include <functional> 11 #include <numeric> 12 #include <sstream> 13 #include <stack> 14 #include <map> 15 #include <queue> 16 #pragma comment(linker, "/STACK:102400000,102400000") 17 #define CL(arr, val) memset(arr, val, sizeof(arr)) 18 19 #define ll long long 20 #define inf 0x7f7f7f7f 21 #define lc l,m,rt<<1 22 #define rc m + 1,r,rt<<1|1 23 #define pi acos(-1.0) 24 25 #define L(x) (x) << 1 26 #define R(x) (x) << 1 | 1 27 #define MID(l, r) (l + r) >> 1 28 #define Min(x, y) (x) < (y) ? (x) : (y) 29 #define Max(x, y) (x) < (y) ? (y) : (x) 30 #define E(x) (1 << (x)) 31 #define iabs(x) (x) < 0 ? -(x) : (x) 32 #define OUT(x) printf("%I64d ", x) 33 #define lowbit(x) (x)&(-x) 34 #define Read() freopen("a.txt", "r", stdin) 35 #define Write() freopen("b.txt", "w", stdout); 36 #define maxn 1000000000 37 #define N 500 38 using namespace std; 39 40 int dp[N][N]; 41 int main() 42 { 43 int n; 44 scanf("%d",&n); 45 for(int i=0;i<n;i++) 46 for(int j=0;j<=i;j++) scanf("%d",&dp[i][j]); 47 for(int i=n-2;i>=0;i--) 48 for(int j=0;j<=i;j++) 49 dp[i][j]=dp[i][j]+max(dp[i+1][j],dp[i+1][j+1]); 50 printf("%d ",dp[0][0]); 51 return 0; 52 }
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。
1 #include <iostream> 2 #include <cstdio> 3 #include <cmath> 4 #include <vector> 5 #include <cstring> 6 #include <string> 7 #include <algorithm> 8 #include <string> 9 #include <set> 10 #include <functional> 11 #include <numeric> 12 #include <sstream> 13 #include <stack> 14 #include <map> 15 #include <queue> 16 #pragma comment(linker, "/STACK:102400000,102400000") 17 #define CL(arr, val) memset(arr, val, sizeof(arr)) 18 19 #define ll long long 20 #define inf 0x7f7f7f7f 21 #define lc l,m,rt<<1 22 #define rc m + 1,r,rt<<1|1 23 #define pi acos(-1.0) 24 25 #define L(x) (x) << 1 26 #define R(x) (x) << 1 | 1 27 #define MID(l, r) (l + r) >> 1 28 #define Min(x, y) (x) < (y) ? (x) : (y) 29 #define Max(x, y) (x) < (y) ? (y) : (x) 30 #define E(x) (1 << (x)) 31 #define iabs(x) (x) < 0 ? -(x) : (x) 32 #define OUT(x) printf("%I64d ", x) 33 #define lowbit(x) (x)&(-x) 34 #define Read() freopen("a.txt", "r", stdin) 35 #define Write() freopen("b.txt", "w", stdout); 36 #define maxn 1000000000 37 #define N 500 38 using namespace std; 39 40 int dp[N]; 41 int main() 42 { 43 //Read(); 44 int n,a,r=0; 45 scanf("%d",&n); 46 for(int i=1;i<=n;i++) 47 { 48 for(int j=i;j>=1;j--) 49 { 50 scanf("%d",&a); 51 dp[j]=max(dp[j],dp[j-1])+a; 52 r=max(r,dp[j]); 53 //printf("%d ",dp[j]); 54 } 55 //printf(" "); 56 } 57 printf("%d ",r); 58 return 0; 59 }