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#include <iostream>
#include <cstring>
void skipWhitespaces(char*& str) {
while (*str == ' ') str++;
}
int calculateExpression(char*& expr) {
if (*expr == '\0') return 0;
skipWhitespaces(expr);
// Ако започваме с цифра, връщаме числото и го пропускаме в израза
if ('0' <= expr[0] && expr[0] <= '9') {
int ret = atoi(expr);
while ('0' <= *expr && *expr <= '9') expr++;
return ret;
}
expr++; // пропускаме (
int leftHandSide = calculateExpression(expr);
skipWhitespaces(expr);
char op = *expr;
expr++;
skipWhitespaces(expr);
int rightHandSide = calculateExpression(expr);
skipWhitespaces(expr);
expr++; // пропускаме )
if (op == '+') {
return leftHandSide + rightHandSide;
}
return leftHandSide * rightHandSide;
}
int main() {
char buf[1025];
std::cin.getline(buf, 1025);
char* ptrCopy = buf;
std::cout << calculateExpression(ptrCopy) << std::endl;
}
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