init

Makefile

@@ -0,0 +1,29 @@
+# Компилятор
+CXX = g++
+
+# Флаги
+CXXFLAGS = -Wall -Wextra -O2 -std=c++17
+
+# Линковка (для shm, fork, etc.)
+LDFLAGS = -lrt
+
+# Имя программы
+TARGET = lab1
+
+# Исходник
+SRC = main.cpp
+
+# ==========================
+
+all: $(TARGET)
+
+$(TARGET): $(SRC)
+	$(CXX) $(CXXFLAGS) $(SRC) -o $(TARGET) $(LDFLAGS)
+
+run: $(TARGET)
+	./$(TARGET)
+
+clean:
+	rm -f $(TARGET)
+
+rebuild: clean all

main.cpp

@@ -0,0 +1,126 @@
+#include <iostream>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <sys/time.h>
+#include <cstdlib>
+
+using namespace std;
+
+#define MAX 100000
+#define MAX_DEPTH 3
+
+struct SharedData {
+    int arr[MAX];
+};
+
+// ================= MERGE =================
+void merge(int *arr, int l, int m, int r) {
+    int *temp = new int[r - l + 1];
+
+    int i = l, j = m + 1, k = 0;
+
+    while (i <= m && j <= r) {
+        if (arr[i] < arr[j])
+            temp[k++] = arr[i++];
+        else
+            temp[k++] = arr[j++];
+    }
+
+    while (i <= m) temp[k++] = arr[i++];
+    while (j <= r) temp[k++] = arr[j++];
+
+    for (int x = 0; x < k; x++)
+        arr[l + x] = temp[x];
+
+    delete[] temp;
+}
+
+// ================= LOCAL SORT =================
+void local_sort(int *arr, int l, int r) {
+    if (l >= r) return;
+    int m = (l + r) / 2;
+    local_sort(arr, l, m);
+    local_sort(arr, m + 1, r);
+    merge(arr, l, m, r);
+}
+
+// ================= PARALLEL SORT =================
+void parallel_sort(int *arr, int l, int r, int depth) {
+    if (l >= r) return;
+
+    int m = (l + r) / 2;
+
+    cout << "PID " << getpid()
+         << " depth=" << depth
+         << " range=[" << l << "," << r << "]\n";
+
+    if (depth >= MAX_DEPTH) {
+        local_sort(arr, l, r);
+        return;
+    }
+
+    pid_t left = fork();
+
+    if (left == 0) {
+        parallel_sort(arr, l, m, depth + 1);
+        _exit(0);
+    }
+
+    pid_t right = fork();
+
+    if (right == 0) {
+        parallel_sort(arr, m + 1, r, depth + 1);
+        _exit(0);
+    }
+
+    waitpid(left, NULL, 0);
+    waitpid(right, NULL, 0);
+
+    merge(arr, l, m, r);
+}
+
+// ================= MAIN =================
+int main() {
+    key_t key = ftok("shmfile", 65);
+    int shmid = shmget(key, sizeof(SharedData), 0666 | IPC_CREAT);
+
+    SharedData *data = (SharedData*) shmat(shmid, (void*)0, 0);
+
+    int n = 20000;
+
+    srand(time(NULL));
+
+    for (int i = 0; i < n; i++)
+        data->arr[i] = rand() % 100000;
+
+    timeval start, end;
+
+    gettimeofday(&start, NULL);
+
+    parallel_sort(data->arr, 0, n - 1, 0);
+
+    gettimeofday(&end, NULL);
+
+    double time_spent =
+        (end.tv_sec - start.tv_sec) +
+        (end.tv_usec - start.tv_usec) / 1e6;
+
+    cout << "\nExecution time: " << time_spent << " sec\n";
+
+    // Проверка
+    for (int i = 1; i < n; i++) {
+        if (data->arr[i - 1] > data->arr[i]) {
+            cout << "ERROR: not sorted!\n";
+            break;
+        }
+    }
+
+    cout << "Sorted correctly\n";
+
+    shmdt(data);
+    shmctl(shmid, IPC_RMID, NULL);
+
+    return 0;
+}