Update 15_Numbers_Histogram.cpp

Author: imdaxsh

C++/15_Numbers_Histogram.cpp

@@ -1,22 +1,65 @@
-#include <bits/stdc++.h>
-using namespace std;
+/*
+firstly we will define all the possible cases between 1 to 1000000 .
+then we will take two integer input of num1 and num2 .
+then possibly create an for loop and run the loop from num1 to num2 
+then for every value of i check the condition  "luckyNumber[i] == 1"
+if true then cout/print i.
+and raise the  value of flag ==1 .
+else if flag == 0 , then return -1 ;
+
+hence solved .
+*/
 
+
+#include<iostream>
+using namespace std;
 int main()
 {
-    char ch;
-    cin >> ch; //input character
-    int n;
-    cin >> n;
-    vector<int> v(n); 
-    for (int i = 0; i < n; i++)
-        cin >> v[i];   //input
-    for (auto i : v)             
-    {
-        for (int j = 0; j < i; j++)
-        {
-            cout << ch; //printing the character Xi times
-        }
-        cout << endl;
+    int luckyNumber[100000]={0} , flag =0;
+    luckyNumber[4]=1;
+    luckyNumber[7]=1;
+    luckyNumber[44]=1;
+    luckyNumber[47]=1;
+    luckyNumber[74]=1;
+    luckyNumber[77]=1;
+    luckyNumber[444]=1;
+    luckyNumber[447]=1;
+    luckyNumber[474]=1;
+    luckyNumber[477]=1;
+    luckyNumber[774]=1;
+    luckyNumber[777]=1;
+    luckyNumber[747]=1;
+   luckyNumber[744]=1;
+   luckyNumber[4747]=1;
+   luckyNumber[4444]=1;
+   luckyNumber[4447]=1;
+   luckyNumber[4474]=1;
+   luckyNumber[4477]=1;
+   luckyNumber[4777]=1;
+   luckyNumber[4744]=1;
+   luckyNumber[4774]=1;
+   luckyNumber[7474]=1;
+   luckyNumber[7777]=1;
+   luckyNumber[7774]=1;
+   luckyNumber[7747]=1;
+   luckyNumber[7744]=1;
+   luckyNumber[4477]=1;
+   luckyNumber[7444]=1;
+   luckyNumber[7477]=1;
+   luckyNumber[7447]=1;
+
+   int num1, num2;
+   cin>>num1 >> num2;
+   for(int i= num1 ;i <=num2;i++){
+    if(luckyNumber[i] == 1){
+        cout << i << " ";
+         flag=1;
     }
-    return 0;
-}
+   }
+   if(flag == 0){
+    cout << "-1" << endl;
+   }
+}
+
+
+// happy coding :)