Merge pull request kothariji#598 from Hilbertmf/master

create (LEETCODE)ugly-number-ii.cpp

Author: kothariji

Dynamic Programming/(LEETCODE)ugly-number-ii.cpp

@@ -0,0 +1,32 @@
+#define INFINITE 0x3f3f3f3f
+class Solution {
+public:
+    
+    int nthUglyNumber(int n) {
+        int ugly_nums[10010];
+	    int power_2 = 1, power_3 = 1, power_5 = 1,
+        next_mul_2, next_mul_3, next_mul_5;
+    	
+    	for(int i=2;i <= n;i++)
+    		ugly_nums[i] = INFINITE;
+    	ugly_nums[1] = 1;
+    	
+    	for(int i=2;i<=n;i++)
+    	{
+    		next_mul_2 = ugly_nums[power_2]*2;
+    		next_mul_3 = ugly_nums[power_3]*3;
+    		next_mul_5 = ugly_nums[power_5]*5;
+    		
+    		ugly_nums[i] = min({next_mul_2, next_mul_3, next_mul_5});
+    		
+    		// increment the power of chosen prime
+    		if(ugly_nums[i] == next_mul_2)
+    				power_2++;
+    		if(ugly_nums[i] == next_mul_3)
+    				power_3++;
+    		if(ugly_nums[i] == next_mul_5)
+    				power_5++;
+    	}
+	    return ugly_nums[n];
+    }
+};