Oil Deposits hdu-1241 DFS
InputThe input file contains one or more grids. Each grid begins with a line containing m and n, the number of rows and columns in the grid, separated by a single space. If m = 0 it signals the end of the input; otherwise 1 <= m <= 100 and 1 <= n <= 100. Following this are m lines of n characters each (not counting the end-of-line characters). Each character corresponds to one plot, and is either `*‘, representing the absence of oil, or `@‘, representing an oil pocket.
OutputFor each grid, output the number of distinct oil deposits. Two different pockets are part of the same oil deposit if they are adjacent horizontally, vertically, or diagonally. An oil deposit will not contain more than 100 pockets.
Sample Input
1 1 * 3 5 *@*@* **@** *@*@* 1 8 @@****@* 5 5 ****@ *@@*@ *@**@ @@@*@ @@**@ 0 0
Sample Output
0 1 2 2
DFS 最基本的題目 兩個for循環,如果地圖上出現@,那麽把他變成*,用遞歸查找他附近的@,直到找不到為止。
1 #include <iostream> 2 using namespace std; 3 #include<string.h> 4 #include<set> 5 #include<stdio.h> 6 #include<math.h> 7View Code#include<queue> 8 #include<map> 9 #include<algorithm> 10 #include<cstdio> 11 #include<cmath> 12 #include<cstring> 13 #include <cstdio> 14 #include <cstdlib> 15 #include<stack> 16 char a[110][110]; 17 int b[8][2]={1,0,-1,0,0,1,0,-1,1,1,1,-1,-1,1,-1,-1}; 18 int n,m; 19 int sum=0; 20 void dfs(int x,int y) 21 { 22 a[x][y]=‘*‘; 23 //cout<<x<<"_"<<y<<"_"<<sum<<endl; 24 for(int i=0;i<8;i++) 25 { 26 if(x+b[i][0]>0&&x+b[i][0]<=n&&y+b[i][1]>0&&y+b[i][1]<=m&&a[x+b[i][0]][y+b[i][1]]==‘@‘) 27 { 28 int x1,y1; 29 x1=x+b[i][0]; 30 y1=y+b[i][1]; 31 dfs(x1,y1); 32 } 33 } 34 35 return ; 36 } 37 int main() 38 { 39 while(scanf("%d%d",&n,&m),n,m) 40 { 41 for(int i=1;i<=n;i++) 42 for(int j=1;j<=m;j++) 43 cin>>a[i][j]; 44 sum=0; 45 for(int i=1;i<=n;i++) 46 for(int j=1;j<=m;j++) 47 { 48 if(a[i][j]==‘@‘) 49 { 50 sum++; 51 dfs(i,j); 52 } 53 } 54 printf("%d\n",sum); 55 } 56 return 0; 57 }
優化了輸入 時間變0.
1 #include <iostream> 2 using namespace std; 3 #include<string.h> 4 #include<set> 5 #include<stdio.h> 6 #include<math.h> 7 #include<queue> 8 #include<map> 9 #include<algorithm> 10 #include<cstdio> 11 #include<cmath> 12 #include<cstring> 13 #include <cstdio> 14 #include <cstdlib> 15 #include<stack> 16 char a[110][110]; 17 int b[8][2]={1,0,-1,0,0,1,0,-1,1,1,1,-1,-1,1,-1,-1}; 18 int n,m; 19 int sum=0; 20 void dfs(int x,int y) 21 { 22 a[x][y]=‘*‘; 23 //cout<<x<<"_"<<y<<"_"<<sum<<endl; 24 for(int i=0;i<8;i++) 25 { 26 if(x+b[i][0]>0&&x+b[i][0]<=n&&y+b[i][1]>0&&y+b[i][1]<=m&&a[x+b[i][0]][y+b[i][1]]==‘@‘) 27 { 28 int x1,y1; 29 x1=x+b[i][0]; 30 y1=y+b[i][1]; 31 dfs(x1,y1); 32 } 33 } 34 35 return ; 36 } 37 int main() 38 { 39 while(scanf("%d%d",&n,&m),n,m) 40 { 41 for(int i=1;i<=n;i++) 42 scanf("%s",a[i]+1); 43 sum=0; 44 for(int i=1;i<=n;i++) 45 for(int j=1;j<=m;j++) 46 { 47 if(a[i][j]==‘@‘) 48 { 49 sum++; 50 dfs(i,j); 51 } 52 } 53 printf("%d\n",sum); 54 } 55 return 0; 56 }View Code
Oil Deposits hdu-1241 DFS