Matrix
Time Limit: 3000MS | Memory Limit: 65536K | |
Total Submissions: 16950 | Accepted: 6369 |
Description
Given an N*N matrix A, whose elements are either 0 or 1. A[i, j] means the number in the i-th row and j-th column. Initially we have A[i, j] = 0 (1 <= i, j <= N).
We can change the matrix in the following way. Given a rectangle whose upper-left corner is (x1, y1) and lower-right corner is (x2, y2), we change all the elements in the rectangle by using "not" operation (if it is a '0' then change it into '1' otherwise change it into '0'). To maintain the information of the matrix, you are asked to write a program to receive and execute two kinds of instructions.
1. C x1 y1 x2 y2 (1 <= x1 <= x2 <= n, 1 <= y1 <= y2 <= n) changes the matrix by using the rectangle whose upper-left corner is (x1, y1) and lower-right corner is (x2, y2).
2. Q x y (1 <= x, y <= n) querys A[x, y].
We can change the matrix in the following way. Given a rectangle whose upper-left corner is (x1, y1) and lower-right corner is (x2, y2), we change all the elements in the rectangle by using "not" operation (if it is a '0' then change it into '1' otherwise change it into '0'). To maintain the information of the matrix, you are asked to write a program to receive and execute two kinds of instructions.
1. C x1 y1 x2 y2 (1 <= x1 <= x2 <= n, 1 <= y1 <= y2 <= n) changes the matrix by using the rectangle whose upper-left corner is (x1, y1) and lower-right corner is (x2, y2).
2. Q x y (1 <= x, y <= n) querys A[x, y].
Input
The first line of the input is an integer X (X <= 10) representing the number of test cases. The following X blocks each represents a test case.
The first line of each block contains two numbers N and T (2 <= N <= 1000, 1 <= T <= 50000) representing the size of the matrix and the number of the instructions. The following T lines each represents an instruction having the format "Q x y" or "C x1 y1 x2 y2", which has been described above.
The first line of each block contains two numbers N and T (2 <= N <= 1000, 1 <= T <= 50000) representing the size of the matrix and the number of the instructions. The following T lines each represents an instruction having the format "Q x y" or "C x1 y1 x2 y2", which has been described above.
Output
For each querying output one line, which has an integer representing A[x, y].
There is a blank line between every two continuous test cases.
There is a blank line between every two continuous test cases.
Sample Input
1 2 10 C 2 1 2 2 Q 2 2 C 2 1 2 1 Q 1 1 C 1 1 2 1 C 1 2 1 2 C 1 1 2 2 Q 1 1 C 1 1 2 1 Q 2 1
Sample Output
1 0 0 1
Source
POJ Monthly,Lou Tiancheng
代码:
采用树状数组第二种方法
采用更新向下,统计向上的方法....楼教主这道题出的还是比较新颖的......
代码:438ms
1 #include<stdio.h> 2 #include<string.h> 3 #include<stdlib.h> 4 #define maxn 1005 5 #define lowbit(x) ((x)&(-x)) 6 int aa[maxn][maxn]; 7 int nn; 8 void ope(int x ,int y ,int val) 9 { 10 for(int i=x ;i>0 ;i-=lowbit(i)) 11 { 12 for(int j=y ;j>0 ;j-=lowbit(j)) 13 { 14 aa[i][j]+=val; 15 } 16 } 17 } 18 int clac(int x,int y) 19 { 20 int ans=0; 21 for(int i=x;i<=nn ;i+=lowbit(i)) 22 { 23 for(int j=y ;j<=nn ;j+=lowbit(j)) 24 { 25 ans+=aa[i][j]; 26 } 27 } 28 return ans; 29 } 30 struct node 31 { 32 int x; 33 int y; 34 }; 35 36 int main() 37 { 38 int tt,xx; 39 char str[5]; 40 node sa,sb; 41 scanf("%d",&xx); 42 while(xx--) 43 { 44 memset(aa,0,sizeof(aa)); 45 scanf("%d%d",&nn,&tt); 46 while(tt--) 47 { 48 scanf("%s",&str); 49 if(str[0]=='C') 50 { 51 scanf("%d%d%d%d",&sa.x,&sa.y,&sb.x,&sb.y); 52 sa.x--; //左上角全体加1 53 sa.y--; 54 ope(sb.x,sb.y,1); 55 ope(sa.x,sb.y,-1); 56 ope(sb.x,sa.y,-1); 57 ope(sa.x,sa.y,1); 58 } 59 else 60 { 61 scanf("%d%d",&sa.x,&sa.y); 62 printf("%d ",clac(sa.x,sa.y)&1); 63 } 64 } 65 printf(" "); 66 } 67 return 0; 68 }
改进版..
代码:
1 #include<stdio.h> 2 #include<string.h> 3 #include<stdlib.h> 4 #define maxn 1005 5 #define lowbit(x) ((x)&(-x)) 6 int aa[maxn][maxn]; 7 int nn; 8 void ope(int x ,int y ) 9 { 10 for(int i=x ;i>0 ;i-=lowbit(i)) 11 { 12 for(int j=y ;j>0 ;j-=lowbit(j)) 13 { 14 aa[i][j]=aa[i][j]^1; 15 } 16 } 17 } 18 int clac(int x,int y) 19 { 20 int ans=0; 21 for(int i=x;i<=nn ;i+=lowbit(i)) 22 { 23 for(int j=y ;j<=nn ;j+=lowbit(j)) 24 { 25 ans+=aa[i][j]; 26 } 27 } 28 return ans; 29 } 30 struct node 31 { 32 int x; 33 int y; 34 }; 35 36 int main() 37 { 38 int tt,xx; 39 char str[5]; 40 node sa,sb; 41 scanf("%d",&xx); 42 while(xx--) 43 { 44 memset(aa,0,sizeof(aa)); 45 scanf("%d%d",&nn,&tt); 46 while(tt--) 47 { 48 scanf("%s",&str); 49 if(str[0]=='C') 50 { 51 scanf("%d%d%d%d",&sa.x,&sa.y,&sb.x,&sb.y); 52 sa.x--; //左上角全体加1 53 sa.y--; 54 ope(sb.x,sb.y); 55 ope(sa.x,sb.y); 56 ope(sb.x,sa.y); 57 ope(sa.x,sa.y); 58 } 59 else 60 { 61 scanf("%d%d",&sa.x,&sa.y); 62 printf("%d ",clac(sa.x,sa.y)&1); 63 } 64 } 65 printf(" "); 66 } 67 return 0; 68 }
采用树状数组第一种方法
传统的方法:
代码:435ms
1 #include<stdio.h> 2 #include<string.h> 3 #include<stdlib.h> 4 #define maxn 1005 5 #define lowbit(x) ((x)&(-x)) 6 int aa[maxn][maxn]; 7 int nn; 8 void ope(int x ,int y ) 9 { 10 for(int i=x ;i<=nn ;i+=lowbit(i)) 11 for(int j=y ;j<=nn ;j+=lowbit(j)) 12 aa[i][j]=aa[i][j]^1; 13 } 14 int clac(int x,int y) 15 { 16 int ans=0,i,j; 17 for(i=x;i>0 ;i-=lowbit(i)) 18 for(j=y ;j>0 ;j-=lowbit(j)) 19 ans+=aa[i][j]; 20 return ans; 21 } 22 struct node 23 { 24 int x,y; 25 }; 26 int main() 27 { 28 int tt,xx; 29 char str[5]; 30 node sa,sb; 31 scanf("%d",&xx); 32 while(xx--) 33 { 34 memset(aa,0,sizeof(aa)); 35 scanf("%d%d",&nn,&tt); 36 while(tt--) 37 { 38 scanf("%s",&str); 39 if(str[0]=='C') 40 { 41 scanf("%d%d%d%d",&sa.x,&sa.y,&sb.x,&sb.y); 42 sb.x++; //左上角全体加1 43 sb.y++; 44 ope(sb.x,sb.y); 45 ope(sa.x,sb.y); 46 ope(sb.x,sa.y); 47 ope(sa.x,sa.y); 48 } 49 else 50 { 51 scanf("%d%d",&sa.x,&sa.y); 52 printf("%d ",clac(sa.x,sa.y)&1); 53 } 54 } 55 printf(" "); 56 } 57 return 0; 58 }