树状数组模板

模板int lowbit(int x){    return x & (-x);}void modify(int x,int add)//一维{      while(x<=MAXN)      {              a[x]+=add;            x+=lowbit(x);     }}int get_sum(int x){      int ret=0;     while(x!=0)      {               ret+=a[x];           x-=lowbit(x);       }      return ret;}void modify(int x,int y,int data)//二维{    for(int i=x;i<MAXN;i+=lowbit(i))        for(int j=y;j<MAXN;j+=lowbit(j))            a[i][j]+=data;}int get_sum(int x,int y){    int res=0;    for(int i=x;i>0;i-=lowbit(i))        for(int j=y;j>0;j-=lowbit(j))            res+=a[i][j];    return res;}