1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177
| import java.util.Scanner;
public class SegmentTree {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in); System.out.println("请输入数组长度:"); int n = sc.nextInt(); int data[] = new int[n + 1]; int tree[] = new int[(n + 1) * 4]; int lazyTag[] = new int[(n + 1) * 4]; System.out.println("请输入数组内的值:"); for (int i = 1; i <= n; ++i) { data[i] = sc.nextInt(); } build(tree, data, 1, 1, n);
System.out.println("请输入需要查询的区间:"); int start = sc.nextInt(); int end = sc.nextInt(); System.out.println(query(tree, lazyTag, start, end, 1, 1, n));
System.out.println("请输入需要更新的区间以及更新的值为多少:"); start = sc.nextInt(); end = sc.nextInt(); int v = sc.nextInt(); update(tree,lazyTag,start,end,1,n,1,v);
System.out.println("请输入需要查询的区间:"); start = sc.nextInt(); end = sc.nextInt(); System.out.println(query(tree, lazyTag, start, end, 1, 1, n));
}
public static int ls(int p) { return p << 1; }
public static int rs(int p) { return p << 1 | 1; }
public static void pushUp(int tree[], int p) { tree[p] = tree[ls(p)] + tree[rs(p)]; }
public static void build(int tree[], int data[], int p, int left, int right) { if (left == right) { tree[p] = data[left]; return; }
int mid = (left + right) >> 1; build(tree, data, ls(p), left, mid); build(tree, data, rs(p), mid + 1, right); pushUp(tree, p); }
public static int query(int tree[], int lazyTag[], int L, int R, int p, int ls, int rs) { if (L <= ls && R >= rs) return tree[p]; pushDown(tree, lazyTag, ls, rs, p); int res = 0; int mid = (ls + rs) >> 1; if (L <= mid) res += query(tree, lazyTag, L, R, ls(p), ls, mid); if (R > mid) res += query(tree, lazyTag, L, R, rs(p), mid + 1, rs); return res; }
public static void addTag(int tree[], int lazyTag[], int ls, int rs, int p, int v) { lazyTag[p] += v; tree[p] += v * (rs - ls + 1); }
public static void pushDown(int tree[], int lazyTag[], int ls, int rs, int p) { if (lazyTag[p] == 0) return;
int mid = (ls + rs) >> 1; addTag(tree, lazyTag, ls, mid, ls(p), lazyTag[p]); addTag(tree, lazyTag, mid + 1, rs, rs(p), lazyTag[p]); lazyTag[p] = 0; }
public static void update(int tree[], int lazyTag[], int L, int R, int ls, int rs, int p, int v) { if (L <= ls && R >= rs) { addTag(tree, lazyTag, ls, rs, p, v); return; } pushDown(tree,lazyTag,ls,rs,p); int mid = (ls+rs)>>1; if (L<=mid) update(tree,lazyTag,L,R,ls,mid,ls(p),v); if(R > mid) update(tree,lazyTag,L,R,mid+1,rs,rs(p),v); pushUp(tree,p); }
}
|