http://acm.sdut.edu.cn/sdutoj/problem.php?action=showproblem&problemid=2080
最长公共子序列
状态方程
if ( ci==cj)
dp[i][j] = dp[i-1][j-1]+1;
else
dp[i][j] = max{dp[i-1][j],dp[i][j-1]};
View Code
1 #include <iostream> 2 #include<cstdio> 3 #include<string.h> 4 using namespace std; 5 int main() 6 { 7 int i,j,k,n,m,dp[501][501],k1,k2; 8 char c1[501],c2[501]; 9 while(gets(c1)!=NULL) 10 { 11 gets(c2); 12 k1 = strlen(c1); 13 k2 = strlen(c2); 14 for(i = 0 ; i < k1 ; i++) 15 dp[i][0] =0; 16 for(j = 0 ;j <= k2 ; j++) 17 dp[0][j] = 0; 18 for(i = 1 ; i <= k1 ; i++) 19 { 20 for(j =1 ; j <= k2 ; j++) 21 if(c1[i-1]==c2[j-1]) 22 dp[i][j] = dp[i-1][j-1]+1; 23 else 24 { 25 if(dp[i][j-1]<dp[i-1][j]) 26 dp[i][j] = dp[i-1][j]; 27 else 28 dp[i][j] = dp[i][j-1]; 29 } 30 } 31 printf("%d\n",dp[k1][k2]); 32 } 33 return 0; 34 }
最长上升子序列
View Code
1 #include <iostream> 2 #include<cstdio> 3 #include<string.h> 4 using namespace std; 5 int dp[1001]; 6 int main() 7 { 8 int i,j,k,n,m,a[1001]; 9 scanf("%d",&n); 10 for(i = 1; i <= n ; i++) 11 { 12 scanf("%d",&a[i]); 13 } 14 dp[1] =1; 15 int max = 1; 16 for(i = 2; i <= n ;i++) 17 { 18 int tmax =1; 19 for(j = 1; j < i ; j++) 20 { 21 if(a[i]>a[j]&&tmax<dp[j]+1) 22 tmax = dp[j]+1; 23 } 24 dp[i] = tmax; 25 if(dp[i]>max) 26 max = dp[i]; 27 } 28 printf("%d\n",max); 29 return 0; 30 }
http://acm.sdut.edu.cn/sdutoj/problem.php?action=showproblem&problemid=1730
数字三角形
dp[i][j] = max{dp[i+1][j],dp[i+1][j+1]}+a[i][j];
View Code
1 #include <iostream> 2 #include<cstdio> 3 #include<string.h> 4 using namespace std; 5 int main() 6 { 7 int i,j,k,n,dp[101][101],a[101][101]; 8 scanf("%d",&n); 9 for(i = 1; i <= n ; i++) 10 for(j = 1 ; j <= i ; j++) 11 scanf("%d",&a[i][j]); 12 for(i = 1 ; i <= n ;i++) 13 dp[n][i] = a[n][i]; 14 for(i = n-1; i >= 1 ; i--) 15 { 16 for(j = 1; j <= i ; j++) 17 if(dp[i+1][j]>dp[i+1][j+1]) 18 dp[i][j]=a[i][j]+dp[i+1][j]; 19 else 20 dp[i][j] = a[i][j]+dp[i+1][j+1]; 21 } 22 printf("%d\n",dp[1][1]); 23 return 0; 24 }
http://acm.hdu.edu.cn/showproblem.php?pid=1003 最大序列和
View Code
1 #include <iostream> 2 #include<cstdio> 3 #include<string.h> 4 using namespace std; 5 int a[100001]; 6 int main() 7 { 8 int i,j,k = 0,n,m,t,x,y; 9 scanf("%d",&t); 10 while(t--) 11 { 12 k++; 13 scanf("%d",&n); 14 for(i = 1; i <= n ; i++) 15 scanf("%d",&a[i]); 16 int tmax = 0,max = -999,tx = 1,y = 1; 17 for(i = 1; i <= n ; i++) 18 { 19 tmax+=a[i]; 20 if(tmax>max) 21 { 22 max = tmax; 23 x = tx; 24 y = i; 25 } 26 if(tmax<0) 27 { 28 tmax = 0; 29 tx = i+1; 30 } 31 } 32 printf("Case %d:\n",k); 33 printf("%d %d %d\n",max,x,y); 34 if(t!=0) 35 puts(""); 36 } 37 return 0; 38 }
http://www.cnblogs.com/shangyu/archive/2012/04/12/2445021.html