#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
ll const m = 1e7;

int decodeCntItreation(string s, int size) {
  ll *arr = new ll[size + 1]{0};
  arr[0] = arr[1] = 1;
  
  for(ll i = 2; i <= size; i++) {
    if(s[i - 1] - '0' != 0) arr[i] = arr[i - 1] % m;
    
    ll val = (s[i - 2] - '0') * 10 + (s[i - 1] - '0');
    
    if(s[i - 2] - '0' != 0 && val <= 26) {
      arr[i] = (arr[i] + arr[i - 2]) % m;
    }
  }
  
  return arr[size];
}

int decodeCnt(string s, int size, unordered_map<int, int> umap) {
  if(size == 0 || size == 1) return 1;
  
  if(umap[size] != 0) return umap[size];
  
  ll output = 0;
  if(s[size - 1] - '0' != 0) output += decodeCnt(s, size - 1, umap) % m;
  
  ll val = (s[size - 2] - '0') * 10 + (s[size - 1] - '0');
  
  if(val <= 26 && s[size - 2] - '0' != 0) {
    output += decodeCnt(s, size - 2, umap) % m;
  }
  
  umap[size] = output;
  return output;
}

int main() 
{
    int t;
    cin>>t;
    
    while(t--) {
      string s;
      
      cin>>s;
      unordered_map<int, int> umap;
      
			if(s == "0") continue;
      cout<<"Recursive : "<<decodeCnt(s, s.size(), umap)<<" Iterative : "<<decodeCntItreation(s, s.size())<<endl;
    }
    
    return 0;
}
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Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}