19 lines
459 B
Java
19 lines
459 B
Java
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public class LinearEqaulity {
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// number of integer solutions of equality a[0]*x1 + ... + a[n-1]*xn = b, xi >= 0
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public static long countSolutions(int[] a, int b) {
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long[] dp = new long[b + 1];
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dp[0] = 1;
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for (int i = 0; i < a.length; i++) {
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for (int j = a[i]; j <= b; j++) {
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dp[j] += dp[j - a[i]];
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}
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}
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return dp[b];
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}
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public static void main(String[] args) {
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System.out.println(5 == countSolutions(new int[] { 1, 2, 3 }, 5));
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}
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}
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