Simple brainfuck interpreter

brainfuck.cpp

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

using namespace std;

int main(int, char **) {
    const size_t memory_buffer_size = 30000;
    
    unsigned char memory[memory_buffer_size];
    memset(memory, 0, memory_buffer_size);
    
    short caretPos = 0, inputPos = 0;
    
    std::string input;
    std::cin >> input;
    
    while (inputPos < input.length()) {
        switch (input[inputPos]) {
            case '>':
                caretPos++;
                break;
            case '<':
                caretPos--;
                break;
            case '+':
                memory[caretPos]++;
                break;
            case '-':
                memory[caretPos]--;
                break;
            case '.':
                std::cout << memory[caretPos];
                break;
            case ',':
                int temp;
                std::cin >> temp;
                memory[caretPos] = temp % 256;
                break;
            case '[':
                if (memory[caretPos] == 0) {
                    int bracketCnt = 1;
                    inputPos++;
                    while (bracketCnt && inputPos < input.length()) {
                        if (input[inputPos] == ']') bracketCnt--;
                        if (input[inputPos] == '[') bracketCnt++;
                        inputPos++;
                    }
                    assert(bracketCnt == 0);
                }
                break;
            case ']':
                if (memory[caretPos] != 0) {
                    int bracketCnt = 1;
                    inputPos--;
                    while (bracketCnt && inputPos < input.length()) {
                        if (input[inputPos] == ']') bracketCnt++;
                        if (input[inputPos] == '[') bracketCnt--;
                        inputPos--;
                    }
                    assert(bracketCnt == 0);
                }
                break;
            default:
                throw;
        }
        inputPos++;
    }
    
    return 0;
}