#include <iostream>
#include <utility> 
#include <string>
#include <vector>
#include <queue>
using namespace std;

#define N 4
#define M 4

int SearchingChallenge(string strArr[], int arrLength) {
  int  n = arrLength, m = n, steps = 0, food = 0;
  // initial position of charlie
  int init_j = 0;
  int init_i = 0;
  queue<pair<int,int>> q;
  // directions
  vector<int> offsets = {0,-1,0,1,0};
  vector<pair<int,int>> food_nodes;
  //store visited nodes, no need for extra work to be done.
  int visited_nodes[4][4] = {{0}};
  
  // get number of food pieces 
  for(int i = 0; i < m; i++){
    for(int j = 0; j < n ; j++){
      if(strArr[i][j] == 'F')
      {
          food++;
      }
      if(strArr[i][j] == 'C')
      {
        strArr[i][j] = 'O';
        food_nodes.push_back({i,j});
      }
    }
  }
  while(food_nodes.size()>0){
      food_nodes.erase(food_nodes.begin());
      int break_flag=0;
      q.push(food_nodes[0]);
  while(!q.empty()){
      int size = q.size();
      while(size-->0){
      pair<int,int> p = q.front();
      q.pop();
      for(int k = 0; k < 4; k++){
      int ii = p.first + offsets[k], jj = p.second + offsets[k+1];
    /*  if(ii == 0 && jj == 3)
        printf("HI"); */
      if(jj >= 0 && jj < 4 && ii < 4 && ii >=0){
          if(strArr[ii][jj] == 'F'){
             strArr[ii][jj] = 'O';
            while(!q.empty())
                q.pop();
            break_flag=1;
            food--;
            food_nodes.push_back({ii,jj});
            break;
          }
          if(strArr[ii][jj] == 'O')
            q.push({ii,jj});
            
            
            if(strArr[ii][jj] == 'H' && food == 0)
                return ++steps;
        }   
     }
    if(break_flag==1)
        break;
    }
    steps++;
    if(break_flag==1)
        break;
  }
}
  return 0;
}

int main(void) { 
   
  // keep this function call here
  /* Note: In C++ you first have to initialize an array and set 
     it equal to the stdin to test your code with arrays. */

  //passing testcase
  //string A[4] = {"OOOO", "OOFF", "OCHO", "OFOO"};
  //failing testcase
  string A[4] = {"FOOF", "OCOO", "OOOH", "FOOO"}
  int arrLength = sizeof(A) / sizeof(*A);
  cout << SearchingChallenge(A, arrLength);
  return 0;
    
}

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

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
}