HD1556Color the ball(树状数组)
Color the ball
Time Limit: 9000/3000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 13645 Accepted Submission(s): 6850
Problem Description
N个气球排成一排,从左到右依次编号为1,2,3....N.每次给定2个整数a b(a <= b),lele便为骑上他的“小飞鸽"牌电动车从气球a开始到气球b依次给每个气球涂一次颜色。但是N次以后lele已经忘记了第I个气球已经涂过几次颜色了,你能帮他算出每个气球被涂过几次颜色吗?
Input
每个测试实例第一行为一个整数N,(N <= 100000).接下来的N行,每行包括2个整数a b(1 <= a <= b <= N)。
当N = 0,输入结束。
当N = 0,输入结束。
Output
每个测试实例输出一行,包括N个整数,第I个数代表第I个气球总共被涂色的次数。
Sample Input
3
1 1
2 2
3 3
3
1 1
1 2
1 3
0
Sample Output
1 1 1
3 2 1
Author
8600
树状数组搞定的第一题!
1 #include <iostream> 2 #include <cstring> 3 #include <cstdio> 4 #include <algorithm> 5 using namespace std; 6 const int MAX = 100000 + 10; 7 int c[MAX]; 8 int n; 9 int lowbit(int k) 10 { 11 return k & (-k); 12 } 13 void update(int x,int num) 14 { 15 16 while(x <= n) 17 { 18 c[x] += num; 19 x += lowbit(x); 20 } 21 } 22 int sum(int x) 23 { 24 int s = 0; 25 while(x > 0) 26 { 27 s += c[x]; 28 x -= lowbit(x); 29 } 30 return s; 31 } 32 int main() 33 { 34 while(scanf("%d", &n) && n) 35 { 36 int a,b; 37 memset(c,0,sizeof(c)); 38 for(int i = 0; i < n; i++) 39 { 40 scanf("%d%d",&a,&b); 41 update(a,1); 42 update(b + 1,-1); 43 } 44 printf("%d",sum(1)); 45 for(int i = 2; i <= n; i++) 46 printf(" %d",sum(i)); 47 printf("\n"); 48 } 49 return 0; 50 }