#include <iostream>
#include<string.h>
#include<cstring>

using namespace std;


int symbColToNumCol(char* colSym,int length){
	int element=0;
	int sum = 0;

	if (length == 1){
		element = colSym[0];
		element = (element - 'A') + 1;
		sum += element;
	}

	else if (length == 2){
		for (int i = 0; i < length; i++){
			element = colSym[i];
			element = (element - 'A') + 1;
			if (i == 0){
				sum = element * 26;
			}
			else if (i == 1){
				sum += element;
			}
		}
	}
	else{
		for (int i = 0; i < length; i++){
			element = colSym[i];
			element = (element - 'A') + 1;
			if (i == 0){
				sum = (pow(26, 2) * element);
			}
			else if (i == 1){
				sum += (element * 26);
			}
			else{
				sum += element;
			}
		}
	}
	return sum;
}

int main()
{
	const int maxSym = 4;
	char colSym[maxSym];

	cout << "Please, enter column letter with length 1-3 symbols: ";
	int length =0;
	bool correctInput = false;


	while (!correctInput)
	{
		cin >> colSym;
		length = (strlen(colSym));
		correctInput = true;

		for (int i = 0; i <length; i++)
		{
			if (colSym[i] < 'A' || colSym[i]>'Z' || length < 1 || length > 3)
			{
				correctInput = false;
			}
		}

		if (!correctInput)
		{
			cout << "Incorrect input. Please, enter column letter with length 1-3 symbols: ";
		}

	}

	cout << symbColToNumCol(colSym,length);
}