added 4 HackerRank solutions

Author: nandiniguptaz

Arrays/(HACKERRANK) Cavity Map.cpp

@@ -0,0 +1,36 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main()
+{
+    int n, i, j;
+    cin>>n;
+    char ch[n][n];
+    for(i=0; i<n; i++)
+    {
+        for(j=0; j<n; j++)
+            cin>>ch[i][j];
+    }
+    
+    for(i=0; i<n; i++)
+    {
+        for(j=0; j<n; j++)
+        {
+            if((i>=1) && (i<(n-1)) && (j>=1) && (j<(n-1)))
+            {
+            if((ch[i-1][j]<ch[i][j]) && (ch[i+1][j]<ch[i][j]) && (ch[i][j-1]<ch[i][j]) && (ch[i][j+1]<ch[i][j]))
+            
+                    ch[i][j] = 'X';
+            }
+        }
+    }
+    
+    for(i=0; i<n; i++)
+    {
+        for(j=0; j<n; j++)
+            cout<<ch[i][j];
+        cout<<endl;
+    } 
+    return 0;
+}

Arrays/(HACKERRANK) Counting Valleys.cpp

@@ -0,0 +1,24 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main()
+{
+    int n, i, level=0, c=0;
+    cin>>n;
+    char ch[n];
+    cin>>ch;
+    for(i=0; i<n; i++)
+    {
+        if(ch[i]=='D')
+            level = level - 1;
+        else 
+        {
+            level = level + 1;
+            if(level==0)
+                c++;
+        }
+    }
+    cout<<c;
+    return 0;
+}

Arrays/(HACKERRANK) Staircase.cpp

@@ -0,0 +1,20 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int main()
+{
+    int n, i, j;
+    cin>>n;
+    for(i=1; i<=n; i++)
+    {
+        for(j=1; j<=(n-i); j++)
+        {
+            cout<<" ";
+        }
+        for(int a =0; a<i;a++)
+        {
+            cout<<"#";
+        }
+        cout<<endl;
+    }
+}

Arrays/(HACKERRANK) Time Conversion.cpp

@@ -0,0 +1,50 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main()
+{
+    char ch[10], i;
+    cin>>ch;
+    if(ch[8]=='A')
+    {
+        if(ch[0]=='1' && ch[1]=='2')
+        {
+            ch[0]='0';
+            ch[1]='0';
+        }
+        
+    }
+    else
+    {
+        if(ch[0]=='0' && ch[1]<='7')
+        {
+            ch[0]='1';
+            ch[1]= ch[1] + 2;
+        }
+        else if(ch[0]=='0' && ch[1]=='8')
+        {
+            ch[0]='2';
+            ch[1]='0';
+        }
+        else if(ch[0]=='0' && ch[1]=='9')
+        {
+            ch[0]='2';
+            ch[1]='1';
+        }
+        else if(ch[0]=='1' && ch[1]=='0')
+        {
+            ch[0]='2';
+            ch[1] = '2';
+        }
+        else if(ch[0]=='1' && ch[1]=='1')
+        {
+            ch[0]='2';
+            ch[1] = '3';
+        }
+        
+    }
+    for(i=0; i<8; i++)
+        cout<<ch[i];
+    return 0;
+}