#include <math.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <iostream>
#include <conio.h>

using namespace std;


int bin2dec(char *n);
int hex2dec(char *n);
int oct2dec(char *n);
void inputInt(int &n);
bool inBinCheck(char n[]);
bool inOctCheck(char n[]);
bool inHexCheck(char n[]);

int main(){
	bool loop = true;
	char ch;
	char n[20];
	int choice;
	
	while(loop){
		printf("1. Convert binary number to decimal number\n2. Convert octal number to decimal number\n3. Convert hexadecimal number to decimal number\n4. Exit\n");
		printf("Please choose number (1 - 4): ");
		while(1){
			inputInt(choice);
			if(choice >= 1 && choice <= 4) break;
			printf("Wrong input! Try again...\n");
		}
		switch (choice){
			case 1:
				printf("Enter binary number: ");
				while(!inBinCheck(n)) 
					printf("\nPlease input correct form of binary!\nTry again: ");
				printf("Decimal number is: %d", bin2dec(n));
				break;
			case 2:
				printf("Enter octal number: ");
				while(!inOctCheck(n)) 
					printf("\nPlease input correct form of octal!\nTry again: ");
				printf("Decimal number is: %d", oct2dec(n));
				break;
			case 3:
				printf("Enter hexadecimal number: ");
				while(!inHexCheck(n)) 
					printf("\nPlease input correct form of hexadecimal!\nTry again: ");
				printf("Decimal number is: %d", hex2dec(n));
				break;
			case 4: 
				printf("Closing...\nThankyou for using Program!<3");
				exit(1);
				break;
		}
		printf("\nPress enter to continue, Esc to return the main menu\n");
		ch = getch();
		if(ch == 27)
			loop = false;
	}
	printf("\nThankyou for using Program!<3");
}

int bin2dec(char n[]){
    int dec = 0;
    int length = strlen(n) - 1;
   	for(int i = 0, j = length;i < strlen(n); i++, j--){
   		int temp = n[j] - 48;
   		dec += temp * pow(2,i);
	}
    return dec;
}

int hex2dec(char n[]){
    int dec = 0;
    int arrCount = strlen(n) - 1;
   	for(int i = 0, j = arrCount;i < strlen(n); i++, j--){
   		int temp;
		if(isdigit(n[j]))
			temp = n[j] - 48;
		else if(isupper(n[j]))
			temp = n[j] - 55;
		else if(islower(n[j]))
			temp = n[j] - 87;
		
   		dec += temp * pow(16,i);
	}
    return dec;
}

int oct2dec(char n[]){
	int dec = 0;
    int arrCount = strlen(n) - 1;
   	for(int i = 0, j = arrCount;i < strlen(n); i++, j--){
   		int temp;
		temp = n[j] - 48;
		
   		dec += temp * pow(8,i);
	}
    return dec;
}

bool inBinCheck(char n[]){
	gets(n);
	for(int i = 0; i < strlen(n); i++){
		if(n[i] == 48 || n[i] == 49) continue;
		else 
			return false;
	}
	return true;
}

bool inOctCheck(char n[]){
	gets(n);
	for(int i = 0; i < strlen(n); i++){
		if(n[i] >= 48 && n[i] <= 55) continue;
		else return false;
	}
	return true;
}

bool inHexCheck(char n[]){
	gets(n);
	for(int i = 0; i < strlen(n); i++){
		if(n[i] >= 49 && n[i] <= 57) continue;
		else if(n[i] >= 65 && n[i] <= 70) continue;
		else if(n[i] >= 97 && n[i] <= 102) continue;
		else return false;
	}
	return true;
}

void inputInt(int &n){
	bool loop = true;
	while(loop){
		scanf("%d", &n);
		if(!isspace(getchar())){
			fflush(stdin);
			printf("Wrong input! Try again...\n");
//			continue;
		}
		else
			loop = false;
	}
}