added cpp program

exercises/hpc_example.cpp

+
+// C program to illustrate
+// command line arguments
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+#include <iostream>       // std::cout, std::endl
+#include <thread>         // std::this_thread::sleep_for
+#include <chrono>         // std::chrono::seconds
+#include <vector>
+#include <sstream>
+
+int main(int argc,char* argv[])
+{
+
+    std::vector <std::string> sources;
+    int *a;
+    size_t mem = 0;
+    int time = 10;
+    char hostname[HOST_NAME_MAX];
+
+
+    for (int i = 1; i < argc; ++i) {
+        if (std::string(argv[i]) == "-t") {
+            if (i + 1 < argc) { // Make sure we aren't at the end of argv!
+                std::stringstream ss1(argv[++i]);
+                if (!(ss1 >> time))
+                  std::cerr << "Invalid number " << argv[i] << '\n';
+            } else { // Uh-oh, there was no argument to the destination option.
+                  std::cerr << "-t option requires one argument." << std::endl;
+                return 1;
+            }
+        } else if (std::string(argv[i]) == "-m") {
+            if (i + 1 < argc) { // Make sure we aren't at the end of argv!
+                std::stringstream ss2(argv[++i]);
+                if (!(ss2 >> mem))
+                    std::cerr << "Invalid number " << argv[i] << '\n';
+            } else { // Uh-oh, there was no argument to the destination option.
+                  std::cerr << "-m option requires one argument." << std::endl;
+                return 1;
+            }
+        } else {
+            sources.push_back(argv[i]);
+        }
+    }
+
+    int result = gethostname(hostname, HOST_NAME_MAX);
+    std::string hostname2 = hostname;
+
+    std::cout << "Current host is: " + hostname2 << std::endl;
+    std::cout << "Wait time is: " << time << " seconds" << std::endl;
+    std::cout << "Memory usage is: " << mem << "MB" << std::endl;
+
+    long int l = mem * 1024 * 1024;
+
+    a = (int*)calloc(mem, 1024 * 1024);
+    memset(a, 0, mem * 1024 * 1024);
+    std::this_thread::sleep_for (std::chrono::seconds(time));
+    free(a);
+
+    return 0;
+}