Stars HDU - 1541

Posted 2021-02-06 lxy8584099

二位偏序

/*
    CDQ之二位偏序
    树状数组 
    注意x能取到0 总体+1 
*/ 
#include<cstdio>
#include<cstring>
using namespace std;
const int N=32050;
int res,n,x,num[N],s[N];
int lowbit(int x) {return x&-x;} 
void add(int x) {while(x<=32000) s[x]++,x+=lowbit(x);} 
int find(int x) {res=0;while(x) res+=s[x],x-=lowbit(x);return res;} 
int main()
{
    while(scanf("%d",&n)!=EOF) 
    {
        memset(s,0,sizeof(s)),memset(num,0,sizeof(num));
        for(int i=0;i<n;i++)
            scanf("%d%*d",&x),x++,num[find(x)]++,add(x);
        for(int i=0;i<n;i++) printf("%d
",num[i]);
    }
    
    return 0;
}