线段树单点更新个人总结

1.1.单点更新 hdu2795 Billboard

#include <iostream>#include <cstdio>#include <algorithm>#define lint long long#define lson l, m, rt<<1#define rson m+1, r, rt<<1|1using namespace std;const int maxn = 222222;int MAX[maxn<<2];int h, w;int ans[maxn];void pushup(int rt){    MAX[rt] = max(MAX[rt<<1], MAX[rt<<1|1]);    }void build(int l, int r, int rt){     if (l == r) {MAX[rt] = w; return;}     int m = (l+r)>>1;     build(lson);     build(rson);     pushup(rt);}void update(int ap,int sc, int l, int r, int rt){     if(l == r)      {          MAX[rt] = MAX[rt] - sc;          ans[ap] = l;          return;     }     int m = (l+r)>>1;     if(sc <= MAX[rt<<1]) update(ap, sc, lson);     else update(ap, sc, rson);     pushup(rt);}int n;int main(){    memset(ans, 0, sizeof(ans));    while(scanf("%d%d%d", &h, &w, &n) != EOF)    {       if(h>n) h = n;       build(1, h, 1);       int wi;       for(int i = 0; i < n; i++)       {               scanf("%d", &wi);               if(wi > MAX[1]) ans[i] = -1;               else update(i, wi, 1, h, 1);       }       for(int i = 0; i < n; i++)         printf("%d\n", ans[i]);    }    return 0;}

1.2.单点更新 hdu1394 Minimum Inversion Number

#include <cstdio>#include <algorithm>#define lson l, m, rt<<1#define rson m+1, r, rt<<1|1using namespace std;const int maxn = 5555;int sum[maxn<<2];void pushup(int rt){     sum[rt] = sum[rt<<1]+sum[rt<<1|1];}void build(int l ,int r, int rt){     sum[rt] = 0;     if(l == r)  return;     int m = (l+r)>>1;     build(lson);     build(rson);}void update(int p ,int l, int r, int rt){     if(l == r) {sum[rt]++; return;}     int m = (r+l)>>1;     if(p <= m) update(p, lson);     else update(p ,rson);     pushup(rt);} int query(int L, int R, int l, int r, int rt){    if(L <= l && r <= R) return sum[rt];    int m = (l+r)>>1;    int ret = 0;    if(L <= m) ret += query(L, R, lson);    if(m < R) ret += query(L, R, rson);    return ret;}int x[maxn];int n;int main(){    while(scanf("%d", &n) != EOF)    {        build(0, n-1, 1);        int sum = 0;        for(int i = 0; i < n; i++)        {           scanf("%d", &x[i]);           sum += query(x[i],n-1, 0, n-1, 1);           update(x[i], 0, n-1, 1);        }        int ret = sum;        for(int i = 0; i < n; i++)        {            sum += n-x[i]-x[i]-1;            ret = min(sum, ret);        }        printf("%d\n", ret);    }    return 0;}

1.3.单点更新 hdu 1754 I hate it

#include<cstdio>#include <iostream>#include <algorithm>#include <cmath>#include <string>#include <cstring>#include <cstdio>#define lson l, m, rt<<1#define rson m+1, r, rt<<1|1#define mset(a, b) memset(a, b, sizeof(a))using namespace std;const int maxn = 222222;int MAX[maxn<<2];void pushup(int rt){     MAX[rt] = max(MAX[rt<<1], MAX[rt<<1|1]);}  void build(int l, int r, int rt){     if(l == r) {scanf("%d", &MAX[rt]); return;}     int m = (l+r)>>1;     build(lson);     build(rson);     pushup(rt);}void update(int p , int sc, int l ,int r, int rt){     if(l == r) { MAX[rt] = sc; return;}     int m = (l + r)>>1;     if(p <= m) update(p ,sc, lson);     else update(p, sc, rson);     pushup(rt);}int query(int L, int R, int l ,int r, int rt){    if(L <= l && r <= R) return MAX[rt];    int m = (l+r)>>1;    int ret = -1;    if(L <= m) ret = max(ret, query(L, R, lson));    if(m < R) ret = max(ret, query(L, R, rson));    return ret;}int main(){    int N, M;    mset(MAX, 0);    while(~scanf("%d%d", &N, &M))    {       build(1, N, 1);       while(M--)       {          char ch[3];          int a, b;          scanf("%s%d%d",ch, &a, &b);          if(ch[0] == 'Q') printf("%d\n", query(a, b, 1,N, 1));          else update(a, b, 1, N, 1);       }    }    return 0;}

1.4.单店更新 hdu1166 敌兵布阵

#include <cstdio> #define lson l , m , rt << 1#define rson m + 1 , r , rt << 1 | 1const int maxn = 55555;int sum[maxn*3];void PushUP(int rt) {sum[rt] = sum[rt<<1] + sum[rt<<1|1];}void build(int l,int r,int rt) {if (l == r) {scanf("%d",&sum[rt]);return ;}int m = (l + r) >> 1;build(lson);build(rson);PushUP(rt);}void update(int p,int add,int l,int r,int rt) {if (l == r) {sum[rt] += add;return ;}int m = (l + r) >> 1;if (p <= m) update(p , add , lson);else update(p , add , rson);PushUP(rt);}int query(int L,int R,int l,int r,int rt) {if (L <= l && r <= R) {return sum[rt];}int m = (l + r) >> 1;int ret = 0;if (L <= m) ret += query(L , R , lson);if (R > m) ret += query(L , R , rson);return ret;}int main() {int T , n;scanf("%d",&T);for (int cas = 1 ; cas <= T ; cas ++) {printf("Case %d:\n",cas);scanf("%d",&n);build(1 , n , 1);char op[10];while (scanf("%s",op)) {if (op[0] == 'E') break;int a , b;scanf("%d%d",&a,&b);if (op[0] == 'Q') printf("%d\n",query(a , b , 1 , n , 1));else if (op[0] == 'S') update(a , -b , 1 , n , 1);else update(a , b , 1 , n , 1);}}return 0;}

1.5.单点更新  poj 2182 lost cows

#include <iostream>#include <cstdio>#define lson l, m, rt<<1#define rson m+1, r, rt<<1|1 using namespace std;const int maxn = 8005;int num[maxn];int ans[maxn];int n;int sum[maxn<<2];void pushup(int rt){     sum[rt] = sum[rt<<1]+sum[rt<<1|1];}void build(int l ,int r, int rt){     if(l == r) { sum[rt] =1; return;}     int m = (l+r)>>1;     build(lson);     build(rson);     pushup(rt);}void update(int p, int ap, int l, int r, int rt){     if(l == r) { sum[rt] = 0; ans[ap] = l; return;}     int m = (l+r)>>1;     if(p <= sum[rt<<1]) update(p, ap, lson);     else update(p-sum[rt<<1], ap, rson);     pushup(rt);}int main(){    scanf("%d", &n);    memset(ans, 0 , sizeof(ans));    num[1]=0;    for(int i = 2; i <= n; i++)    {       scanf("%d", &num[i]);    }    build(1,n,1);    for(int i = n; i >=1; i--)    {            update(num[i]+1,i,1,n,1);    }    for(int i = 1; i <= n; i++)    {       printf("%d\n", ans[i]);    }    return 0;}