Solved a couple of problems from codechef and codeforces

1 files changed, 31 insertions, 0 deletions

diff --git a/NearlyLuckyNumber/main.cpp b/NearlyLuckyNumber/main.cpp
new file mode 100644
index 0000000..d807b1a
--- /dev/null
+++ b/NearlyLuckyNumber/main.cpp
@@ -0,0 +1,31 @@
+#include<bits/stdc++.h>
+
+using namespace std;
+
+bool isLucky(string s) {
+  for(int i = 0; i < s.size(); i++) {
+    if(s[i] != '4' && s[i] != '7') {
+      return false;
+    }
+  }
+  return true;
+}
+
+int main () {
+	ios_base::sync_with_stdio(false);
+	cin.tie(NULL);
+  long long n;
+  cin >> n;
+  string s = to_string(n);
+  int cnt = 0;
+  for(auto ch : s) {
+    if(ch == '4' || ch == '7') {
+      cnt ++;
+    }
+  }
+  if(isLucky(to_string(cnt))) {
+    cout << "YES";
+  } else {
+    cout << "NO";
+  }
+}