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@ -9,16 +9,17 @@ public class Code05_DistinctSubseqValue {
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if (s == null || s.length() == 0) {
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if (s == null || s.length() == 0) {
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return 0;
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return 0;
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}
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}
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int m = 1000000007;
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long m = 1000000007;
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char[] str = s.toCharArray();
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char[] str = s.toCharArray();
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int[] count = new int[26];
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long[] count = new long[26];
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int all = 1; // 算空集
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long all = 1; // 算空集
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for (char x : str) {
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for (char x : str) {
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int add = (all - count[x - 'a'] + m) % m;
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long add = (all - count[x - 'a'] + m) % m;
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all = (all + add) % m;
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all = (all + add) % m;
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count[x - 'a'] = (count[x - 'a'] + add) % m;
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count[x - 'a'] = (count[x - 'a'] + add) % m;
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}
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}
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return all - 1;
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all = (all - 1 + m) % m;
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return (int) all;
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}
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}
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public static int zuo(String s) {
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public static int zuo(String s) {
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