I tried to multiply 2 positive variables but it turned out negative, how do i fix it?

Question

(Pardon my english) So im new at coding. the main problem on my program is that when I multiply a variable with another variable, it just doesn't work. here is the full program.

#include <iostream>
using namespace std;

class employment {
  private:
    // Private attribute
    int salary;
    

  public:
    // Setter
    void setSalary(int s) {
      salary = s;
    }
   
    
    // Getter
    int getSalary() {
      return salary;
    }
    
};

void divider(int y){
    for(int i=1;i<y; i++){
        cout<<"=============================\n";
    }
}

int main() {
    string name,category, status;
    char penalty,i;
    int penaltyAm, categoryAm;
    
    //Regional division
    employment regionalDiv;
    regionalDiv.setSalary(5000000);
  
    //Administration and warehousing
    employment adminWarehouse;
    adminWarehouse.setSalary(5700000);
  
    //Factory manager
    employment factManager;
    factManager.setSalary(15000000);

    //Marketing manager
    employment marketManager;
    marketManager.setSalary(16000000);

    //Personnel manager
    employment persManager;
    persManager.setSalary(18000000);

    // Other manager
    employment otManager;
    otManager.setSalary(25000000);
    
    //Personnel director
    employment persDirector;
    persDirector.setSalary(35000000);
    
    //Other director
    employment otDirector;
    otDirector.setSalary(40000000);
    
    //Director of finance
    employment finDirector;
    finDirector.setSalary(45000000);
    
    //President director
    employment presDirector;
    presDirector.setSalary(50000000);
    
    //Director
    employment director;
    director.setSalary(60000000);
    
    do{
    //asking for employment category
    divider(3);
    cout<< "Name: ";
    getline(cin,name);
    cout<< "employment category: ";
    getline(cin, category);
    categoryAm=0;
    if(category=="Regional division"){
        cout<< "Salary: "<<regionalDiv.getSalary()<<endl;
        categoryAm= 5000000;
        }
        
        else if(category=="Administration and warehousing"){
        cout<< "Salary: "<<adminWarehouse.getSalary()<<endl;
        categoryAm= 5700000;
        }
        
        else if(category=="Factory manager"){
        cout<< "Salary: "<<factManager.getSalary()<<endl;
        categoryAm= 15000000    ;   
        }
        
        else if(category=="Marketing manager"){
        cout<< "Salary: "<<marketManager.getSalary()<<endl;
        categoryAm= 16000000;
        }
        
        else if(category=="Personnel manager"){
        cout<< "Salary: "<<persDirector.getSalary()<<endl;
        categoryAm= 18000000;       
        }
        
        else if(category=="Other manager"){
        cout<< "Salary: "<<otManager.getSalary()<<endl;
        categoryAm= 25000000;
        }
        
        else if(category=="Personnel director"){
        cout<< "Salary: "<<persDirector.getSalary()<<endl;
        categoryAm= 35000000;       
        }
        
        else if(category=="Other director"){
        cout<< "Salary: "<<otDirector.getSalary()<<endl;
        categoryAm= 40000000;
        }
        
        else if(category=="Director of finance"){
        cout<< "Salary: "<<presDirector.getSalary()<<endl;
        categoryAm= 45000000;       
        }
        
        else if(category=="President director"){
        cout<< "Salary: "<<presDirector.getSalary()<<endl;
        categoryAm= 50000000;
        }
        
        else if(category=="Director"){
        cout<< "Salary: "<<director.getSalary()<<endl;      
        categoryAm= 60000000;
        }
        
        
        cout<<"Penalty(T/F): ";
        cin>> penalty;
        if(penalty=='T'){
            cout<<"Amount of penalty(%): ";
            cin>>penaltyAm;
            penaltyAm=100-penaltyAm;
//          cout<<penaltyAm<<endl;
//          cout<<categoryAm<<endl;
        int moSalary=categoryAm*penaltyAm/100;
            cout<<"This month salary: "<<moSalary<<endl;
        }else{
            cout<<"This month salary: "<<categoryAm<<endl;
        }
        cout<<"Status :";
        cin>>status;
        divider(2);
        cout<<"new data(Y/N) :";
        cin >> i;
        cin.ignore (); 
    }while(i=='Y');
    
    
  return 0;
}

the problem occurs here

cout<<"This month salary: "<<moSalary<<endl;

cin category variable as "Regional division" (aka first if) it just works well.

but when i cin category variable with other than "Regional division", the moSalary variable turned to minus something and that's illogical. Anyway i don't understand the way company works. this is just my excercise.

i tried to change moSalary declaration places but it still fails.

i hope someone can help me to make the moSalary variable works well.

tried 1:

so this is how the program went please look at the "This month salary:.."

when I inputed "Personnel director", it should set categoryAm= 5000000. and I set penalty to Y, means that I should enter the penalty number in percent. i inputed penaltyAm = 10. then I assigned penaltyAm to 100-penaltyAm that is 90 so I can multiply it later.

it should be good but then the output of int moSalary=categoryAm*penaltyAm/100; became minus and I don't understand why.

tried 2: I tried to change moSalary type data into float. it become more confusing for me as I don't have basic knowledge of it. 1.44e+007 what TvT help :"

tried 3: so I tried adding #include<stdint.h> and changing moSalary data type into int64_t and it produced minus number again. Is there anything else I can try? thank you.