56 lines
1.3 KiB
Java
56 lines
1.3 KiB
Java
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class RLEIterator {
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private int[] encoding;
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private int major = 0;
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private int minor = 0;
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public RLEIterator(int[] encoding) {
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this.encoding = encoding;
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}
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private void nextSegment() {
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major += 2;
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minor = 0;
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}
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private int lastConsumed() {
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if (major == 0 && minor == 0) {
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// Haven't consumed anything
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return -1;
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} else if (major <= encoding.length && minor == 0) {
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// Consumed last element of a previous segment
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return encoding[major - 1];
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} else if (major >= encoding.length) {
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// Everything was consumed
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return -1;
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}
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// Last consumed from the current segment
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return encoding[major + 1];
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}
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public int next(int n) {
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while (n > 0 && major < encoding.length) {
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int consumed = Math.min(n, encoding[major] - minor);
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n -= consumed;
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minor += consumed;
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if (minor == encoding[major]) {
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nextSegment();
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}
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}
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if (n > 0) {
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return -1;
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}
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return lastConsumed();
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}
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}
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/**
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* Your RLEIterator object will be instantiated and called as such:
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* RLEIterator obj = new RLEIterator(encoding);
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* int param_1 = obj.next(n);
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*/
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