Initial commit

2022/city/12/expresii/expresii.cpp

@@ -0,0 +1,96 @@
+#include <fstream>
+#include <deque>
+#include <unordered_map>
+using namespace std;
+
+ifstream input_stream;
+ofstream output_stream;
+unordered_map<char, int> numbers_map = {{'I', 1}, {'V', 5}, {'X', 10}, {'L', 50}, {'C', 100}, {'D', 500}, {'M', 1000}};
+
+
+int64_t evaluateNum(string num) {
+    int64_t res = 0;
+    const int lim = num.length();
+
+
+    for (int i = 0; i < lim - 1; i++) {
+        if (numbers_map[num[i]] >= numbers_map[num[i + 1]]) {
+            res += numbers_map[num[i]];
+        } else {
+            res -= numbers_map[num[i]];
+        }
+    }
+    res += numbers_map[num[lim - 1]];
+
+    return res;
+}
+
+
+
+int main() {
+    input_stream.open("expresii.in");
+    output_stream.open("expresii.out");
+
+    string expression;
+    input_stream >> expression;
+
+    deque<int64_t> numbers;
+    deque<char> operations;
+
+    string currNumber = "";
+    const int lim = expression.length();
+    for (int i = 0; i < lim; i++) {
+        if (numbers_map[expression[i]] > 0) {
+            currNumber += expression[i];
+        } else {
+            numbers.push_back(evaluateNum(currNumber));
+            operations.push_back(expression[i]);
+            currNumber = "";
+        }
+    }
+    numbers.push_back(evaluateNum(currNumber));
+
+
+    // Evaluate multiplications
+    int pos = 0;
+    for (auto it = operations.begin(); it != operations.end(); it++) {
+        if (*it == '*') {
+            auto num1 = numbers.begin();
+            advance(num1, pos);
+            auto num2 = numbers.begin();
+            advance(num2, pos + 1);
+
+            *num1 = *num2 * *num1;
+            numbers.erase(num2);
+            pos--;
+        }
+        pos++;
+    }
+
+
+    // Evaluate other stuff
+    pos = 0;
+    int64_t res = numbers.front();
+    for (auto it = operations.begin(); it != operations.end(); it++) {
+        if (*it == '*') {
+            continue;
+        }
+
+        auto num = numbers.begin();
+        advance(num, pos + 1);
+
+        if (*it == '+') {
+            res += *num;
+        } else {
+            res -= *num;
+        }
+
+        pos++;
+    }
+
+    output_stream << res << endl;
+
+    input_stream.close();
+    output_stream.close();
+    return 0;
+}