题目链接
树状数组
#include <iostream>
#include<cstring>
#include<cstdio>
#include<algorithm>
#include<climits>
#include<vector>
#include<queue>
#include<string>
#include <cmath>
#include<set>
#include<map>
#define mod 999997
#define lson l, mid, root << 1
#define rson mid + 1, r, root << 1 | 1
#define father l , r , root
#define lowbit(x) ( x & ( - x ) )
using namespace std;
typedef long long ll;
const int maxn = 51000;
const int inf = 0x3f3f3f3f;
int n;
int num[maxn];
int arr[maxn];
void update(int x,int val){
for(int i=x;i<=n;i+=lowbit(i)){
arr[i]+=val;
}
}
int getsum(int x){
int ans=0;
for(int i=x;i>0;i-=lowbit(i)){
ans+=arr[i];
}
return ans;
}
int main( ){
int t;
char s[10];
scanf("%d",&t);
int cnt=1;
while(t--){
memset(arr,0,sizeof(arr));
printf("Case %d:\n",cnt++);
scanf("%d",&n);
for(int i=1;i<=n;i++){
int val;
scanf("%d",&val);
update(i,val);
}
while(scanf("%s",s)){
if(strcmp(s,"End")==0){
break;
}else if(strcmp(s,"Query")==0){
int l,r;
scanf("%d%d",&l,&r);
printf("%d\n",getsum(r)-getsum(l-1));
}else if(strcmp(s,"Sub")==0){
int pos,val;
scanf("%d%d",&pos,&val);
update(pos,-val);
}else{
int pos,val;
scanf("%d%d",&pos,&val);
update(pos,val);
}
}
}
}
线段树
#include <iostream>
#include<cstring>
#include<cstdio>
#include<algorithm>
#include<climits>
#include<vector>
#include<queue>
#include<string>
#include <cmath>
#include<set>
#define mod 999997
#define lson l, mid, root << 1
#define rson mid + 1, r, root << 1 | 1
#define father l , r , root
#define lowbit(x) ( x & ( - x ) )
using namespace std;
typedef long long ll;
const int maxn = 5e5+5;
const int inf = 0x3f3f3f3f;
int num[maxn];
int node[maxn<<2];
void push_up(int root){
node[root]=node[root<<1]+node[root<<1|1];
}
void build_tree(int l,int r,int root){
if(l==r){
node[root]=num[l];
return ;
}
int mid=(l+r)>>1;
build_tree(lson);
build_tree(rson);
push_up(root);
}
void change(int pos,int val,int l,int r ,int root){
if(l==pos&&r==pos){
node[root]+=val;
return ;
}
int mid=(l+r)>>1;
if(mid>=pos)change(pos,val,lson);
else change(pos,val,rson);
push_up(root);
}
int query(int L,int R,int l,int r ,int root){
if(L<=l&&R>=r){
return node[root];
}
int ans=0;
int mid=(l+r)>>1;
if(mid>=L){
ans+=query(L,R,lson);
}
if(mid<R){
ans+=query(L,R,rson);
}
return ans;
}
int main( ){
int t;
scanf("%d",&t);
char s[10];
int cnt=1;
while(t--){
int n;
scanf("%d",&n);
printf("Case %d:\n",cnt++);
for(int i=1;i<=n;i++)scanf("%d",&num[i]);
build_tree(1,n,1);
while(1){
scanf("%s",s);
if(strcmp(s,"End")==0){
break;
}else if(strcmp(s,"Query")==0){
int l,r;
scanf("%d%d",&l,&r);
printf("%d\n",query(l,r,1,n,1));
}else if(strcmp(s,"Sub")==0){
int pos,val;
scanf("%d%d",&pos,&val);
change(pos,-val,1,n,1);
}else{
int pos,val;
scanf("%d%d",&pos,&val);
change(pos,val,1,n,1);
}
}
}
return 0;
}