HIT-1867-树状数组

来源：互联网发布：mobi 阅读软件编辑：程序博客网时间：2024/06/02 06:45

题解思路：用O（sqrt（n））判断是不是素数，然后直接套数组数组。（我就奇怪了为什么还要C=0这种操作，我判断循环写&&C不行，C+n+m才行）

代码：

#include<algorithm>#include<cstdio>#include<cstring>#include<iostream>#include<cmath>#define lson l,mid,rt<<1#define rson mid+1,r,rt<<1|1#define inf 0x3f3f3f3fusing namespace std;typedef long long ll;const int mx = 1e6+100;int n,m,C,sum[mx],num[mx];inline int lowbit(int x){return x&(-x);}bool vis[mx];bool isprime(int x){if(x<2) return 0;int cnt = sqrt(1.0*x);for(int i=2;i<=cnt;i++)if(x%i==0) return 0;return 1;}void add(int x,int v){for(int i=x;i<=C;i+=lowbit(i))sum[i]+=v;}int getsum(int x){int ans = 0;while(x){ans+=sum[x];x-=lowbit(x);}return ans;}int main(){int cas = 1;while(scanf("%d%d%d",&C,&n,&m)&&C+n+m){bool v = isprime(m);for(int i=1;i<=C;i++) sum[i] = 0, vis[i] = v, num[i] = m;if(v) for(int i=1;i<=C;i++) add(i,v);printf("CASE #%d:\n",cas++);while(n--){int x,y,z;scanf("%d%d%d",&x,&y,&z);if(x) printf("%d\n",getsum(z)-getsum(y-1));else{bool u = isprime(num[y]+z);add(y,u-vis[y]);vis[y] = u;num[y]+=z;}}puts("");}return 0;}

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