Added the code for Grid Challenge problem

Hackerrank/Grid Challenge.cpp

@@ -0,0 +1,58 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+// Complete the gridChallenge function below.
+string gridChallenge(vector<string> Grid) {
+  size_t jj, n = Grid.size();
+    bool is_not = false;
+    for (int i = n-1; i >= 0; i--) {
+        string& r = Grid[i];
+
+        sort(begin(r),end(r));
+
+        if (i == n-1) continue;
+        string& p = Grid[i+1];
+
+         for (int j = 0; j < n; j++) {
+
+             if (int(r[j]) > int(p[j])) {
+                 is_not = true; break;
+             }
+         }
+        if (is_not) break;
+    }
+    return (is_not?"NO":"YES");
+}
+
+int main()
+{
+    ofstream fout(getenv("OUTPUT_PATH"));
+
+    int t;
+    cin >> t;
+    cin.ignore(numeric_limits<streamsize>::max(), '\n');
+
+    for (int t_itr = 0; t_itr < t; t_itr++) {
+        int n;
+        cin >> n;
+        cin.ignore(numeric_limits<streamsize>::max(), '\n');
+
+        vector<string> grid(n);
+
+        for (int i = 0; i < n; i++) {
+            string grid_item;
+            getline(cin, grid_item);
+
+            grid[i] = grid_item;
+        }
+
+        string result = gridChallenge(grid);
+
+        fout << result << "\n";
+    }
+
+    fout.close();
+
+    return 0;
+}