UGLY NUMBERS II

不去重错误版 17.4.23

long isMin (long a, long b) {
if (a >= b)
a = b;
return a;
}
long nthUglyNumber(long n) {
long *l = (long*)malloc(n*sizeof(long));
for (long i = 0; i < n; i++)
l[i] = 0;
l[0] = 1;
long p2, p3, p5 = 0;
for(long i = 0; i < n - 1; i++) {
l[i + 1] = isMin(l[p2] * 2,isMin(l[p3] * 3,l[p5] * 5));
if(l[i + 1] == l[p2]*2)
p2++;
if(l[i + 1] == l[p3]*3)
p3++;
if(l[i + 1] == l[p5]*5)
p5++;
}
return l[n - 1];
}

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17.4.24

java版 AC

public class Solution {
public int nthUglyNumber(int n) {
int[] num = new int[n];
num[0] = 1;
int p2 = 0, p3 = 0, p5 = 0;
for (int i = 1; i < n; i++) {
int min = Math.min(num[p2]*2,Math.min(num[p3]*3, num[p5]*5));
num[i] = min;
if(min == num[p2]*2) p2++;
if(min == num[p3]*3) p3++;
if(min == num[p5]*5) p5++;
}
return num[n - 1];
}
}