Create NextPermutation

java-program/NextPermutation

@@ -0,0 +1,39 @@
+class Solution {
+    public void nextPermutation(int[] nums) {
+
+        int i=nums.length-2;
+        while(i>=0 && nums[i]>=nums[i+1]){
+            i--;
+        }
+
+        if(i>=0)
+        {
+            int j=nums.length-1;
+            while(j>=0 && nums[j]<=nums[i])
+            {
+                j--;
+            }
+            swap(nums,i,j);
+        }
+        reverse(nums,i+1);
+
+    }
+
+    public void swap(int nums[],int i,int j)
+    {
+        int temp=nums[i];
+        nums[i]=nums[j];
+        nums[j]=temp;
+    }
+
+    public void reverse(int nums[],int start)
+    {
+        int end=nums.length-1;
+        while(start<end)
+        {
+            swap(nums,start,end);
+            start++;
+            end--;
+        }
+    }
+}