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34 lines
746 B
Java
34 lines
746 B
Java
public class SegmentTreeSimple {
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public static int get(int[] t, int i) {
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return t[i + t.length / 2];
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}
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public static void add(int[] t, int i, int value) {
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i += t.length / 2;
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t[i] += value;
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for (; i > 1; i >>= 1)
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t[i >> 1] = Math.max(t[i], t[i ^ 1]);
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}
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public static int max(int[] t, int a, int b) {
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int res = Integer.MIN_VALUE;
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for (a += t.length / 2, b += t.length / 2; a <= b; a = (a + 1) >> 1, b = (b - 1) >> 1) {
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if ((a & 1) != 0)
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res = Math.max(res, t[a]);
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if ((b & 1) == 0)
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res = Math.max(res, t[b]);
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}
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return res;
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}
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// Usage example
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public static void main(String[] args) {
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int n = 10;
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int[] t = new int[n + n];
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add(t, 0, 1);
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add(t, 9, 2);
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System.out.println(2 == max(t, 0, 9));
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}
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}
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