Create WildcardPattern.cpp (#890)

Author: engineervt

C++/Data Structure/WildcardPattern.cpp

@@ -0,0 +1,45 @@
+/* Question-:given 2 strings s1 and s2.We have to match string s1 containing (*,?,characters)
+to string s2 containing only characters,*/
+// * can contain characters ranging from 0 to size of string
+// ? can contain single string
+
+#include<bits/stdc++.h>
+using namespace std;
+
+//Done with the help of recursion  
+bool fun(string &pattern, string &text, int i, int j)
+{
+    if (i < 0 && j < 0)  //(Base Case)      //T.C-: O(length of string s2*length of string s2)
+        return true;    //(Base Case)      //S.C-: O(length of string s2*length of string s2 + auxilliary stack space of string s1 and s2)
+    if (i < 0 && j >= 0)
+        return false;
+    if (j < 0 && i >= 0)
+    {
+        for (int i1 = 0; i1 <= i; i1++)
+        {
+            if (pattern[i1] != '*')  //for the edge case if string s2 empty and s1 contains only *
+                return false;
+        }
+        return true;
+    }
+    if (pattern[i] == text[j] || pattern[i] == '?')
+        return fun(pattern, text, i - 1, j - 1);      //Having a similiar character and a ? is same.As ? can be replaced to the required character 
+    if (pattern[i] == '*')
+        return fun(pattern, text, i - 1, j) or fun(pattern, text, i, j - 1);  //first function symbolizes if the * has more than 1 characters
+    return false;                                                             //second function symbolizes if the * has only 1 character  
+}
+bool wildcardMatching(string pattern, string text)
+{
+    // Write your code here.
+    int n = pattern.length();
+    int m = text.length();
+    return fun(pattern, text, n, m);  //calling function
+}
+int main()               //Main Function
+{
+    string s;
+    cin >> s;
+    string s1;
+    cin >> s1;
+    cout << wildcardMatching(s, s1);
+}