added solution to q45

leetCode Solutions/Q45_JumpGame2/Q45_JumpGame2.cpp

@@ -0,0 +1,20 @@
+class Solution {
+public:
+    int jump(vector<int>& nums) {
+        // support variables
+        int len = nums.size(), steps[len];
+        // presetting steps
+        for (int i = 1; i < len; i++) {
+            steps[i] = INT_MAX;
+        }
+        steps[0] = 0;
+        // populating steps with the lowest possible values
+        for (int i = 0; i < len; i++) {
+            for (int lmt = i, j = min(len - 1, i + nums[i]); j > lmt; j--) {
+                if (steps[j] > steps[i] + 1) steps[j] = steps[i] + 1;
+                else break;
+            }
+        }
+        return steps[len - 1];
+    }
+};