简单线段树（模板）
A - I Hate It
模板，单点更新，区间查询
1 #include <iostream> 2 #include <cstring> 3 #include <string> 4 #include <map> 5 #include <set> 6 #include <algorithm> 7 #include <fstream> 8 #include <cstdio> 9 #include <cmath> 10 #include <stack> 11 #include <queue> 12 #define lson l,m,rt<<1 13 #define rson m+1,r,rt<<1|1 14 using namespace std; 15 const double Pi=3.14159265358979323846; 16 typedef long long ll; 17 const int dx[5]={0,0,0,1,-1}; 18 const int dy[5]={1,-1,0,0,0}; 19 const int INF = 0x3f3f3f3f; 20 const int NINF = 0xc0c0c0c0; 21 const int MAXN=200000+5; 22 const ll mod=1e9+7; 23 int tree[MAXN<<2]; 24 //向上更新 25 void PushUp(int rt){ 26 tree[rt]=max(tree[rt<<1],tree[rt<<1|1]); 27 } 28 //建树 29 void build(int l,int r,int rt){ 30 if(l==r){ 31 scanf("%d",&tree[rt]); 32 return; 33 } 34 int m=(l+r)>>1; 35 build(lson);build(rson); 36 PushUp(rt); 37 } 38 //单点更新 39 void update(int p,int add,int l,int r,int rt){ 40 if(l==r){ 41 tree[rt]=add; 42 return; 43 } 44 int m=(l+r)>>1; 45 if(p<=m) update(p,add,lson); 46 else update(p,add,rson); 47 PushUp(rt); 48 } 49 //区间查询 50 int query(int L,int R,int l,int r,int rt){ 51 if(L<=l&&r<=R){ 52 return tree[rt]; 53 } 54 int m=(l+r)>>1; 55 int ret=NINF; 56 if(L<=m) ret=max(ret,query(L,R,lson)); 57 if(R>m) ret=max(ret,query(L,R,rson)); 58 return ret; 59 } 60 61 int main() 62 { 63 int n,m; 64 while(scanf("%d%d",&n,&m)!=EOF) 65 { 66 build(1,n,1); 67 while(m--) 68 { 69 char c;int x,y;cin>>c;scanf("%d%d",&x,&y); 70 if(c=='Q') 71 cout <<query(x,y,1,n,1)<<endl; 72 else update(x,y,1,n,1); 73 } 74 } 75 return 0; 76 }
B - A Simple Problem with Integers
这个题呀，错了个符号，调了半天。区间修改加区间查询
1 #include <iostream> 2 #include <cstring> 3 #include <string> 4 #include <map> 5 #include <set> 6 #include <algorithm> 7 #include <fstream> 8 #include <cstdio> 9 #include <cmath> 10 #include <stack> 11 #include <queue> 12 #define lson l,m,rt<<1 13 #define rson m+1,r,rt<<1|1 14 using namespace std; 15 const double Pi=3.14159265358979323846; 16 typedef long long ll; 17 const int dx[5]={0,0,0,1,-1}; 18 const int dy[5]={1,-1,0,0,0}; 19 const int INF = 0x3f3f3f3f; 20 const int NINF = 0xc0c0c0c0; 21 const int MAXN=100000+5; 22 const ll mod=1e9+7; 23 24 ll tree[MAXN<<2]; 25 ll add[MAXN<<2]; 26 //向上更新 27 void PushUp(int rt){ 28 tree[rt]=tree[rt<<1]+tree[rt<<1|1]; 29 } 30 //向下更新 31 void PushDown(int rt,int m){ 32 if(add[rt]){ 33 add[rt<<1]+=add[rt]; 34 add[rt<<1|1]+=add[rt]; 35 tree[rt<<1]+=add[rt]*(m-(m>>1)); 36 tree[rt<<1|1]+=add[rt]*(m>>1); 37 add[rt]=0; 38 } 39 } 40 //建树 41 void build(int l,int r,int rt){ 42 add[rt]=0; 43 if(l==r){ 44 scanf("%lld",&tree[rt]); 45 return; 46 } 47 int m=(l+r)>>1; 48 build(lson);build(rson); 49 PushUp(rt); 50 } 51 //单点更新 52 void updatePoint(int p,int add,int l,int r,int rt){ 53 if(l==r){ 54 tree[rt]=add; 55 return; 56 } 57 PushDown(rt,r-l+1); 58 int m=(l+r)>>1; 59 if(p<=m) updatePoint(p,add,lson); 60 else updatePoint(p,add,rson); 61 PushUp(rt); 62 } 63 //区间更新 64 void updateQuery(int L,int R,int c,int l,int r,int rt){ 65 if(L<=l&&r<=R){ 66 add[rt]+=c; 67 tree[rt]+=(ll)c*(r-l+1); 68 return; 69 } 70 PushDown(rt,r-l+1); 71 int m=(l+r)>>1; 72 if(L<=m) updateQuery(L,R,c,lson); 73 if(R>m) updateQuery(L,R,c,rson); 74 PushUp(rt); 75 } 76 //区间查询 77 ll query(int L,int R,int l,int r,int rt){ 78 if(L<=l&&r<=R){ 79 return tree[rt]; 80 } 81 PushDown(rt,r-l+1); 82 int m=(l+r)>>1; 83 ll ret=0; 84 if(L<=m) ret+=query(L,R,lson); 85 if(R>m) ret+=query(L,R,rson); 86 return ret; 87 } 88 int main() 89 { 90 int n,m;int cnt=0; 91 //freopen("a.txt","r",stdin); 92 cin>>n>>m; 93 build(1,n,1); 94 while(m--) 95 { 96 char c;ll x,y,z;cin>>c; 97 if(c=='Q') 98 { 99 cnt++; 100 scanf("%lld%lld",&x,&y); 101 cout <<query(x,y,1,n,1)<<endl; 102 }else 103 { cnt++; 104 scanf("%lld%lld%lld",&x,&y,&z); 105 updateQuery(x,y,z,1,n,1); 106 } 107 } 108 return 0; 109 }
