OpenACC: Difference between revisions

OpenACC (view source)

541 bytes added , 3 years ago

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@@ Line 44: / Line 44: @@
    }
    printf("pi = %11.10f\n", pi / N);
+  return 0;
+}
+}}
+</tab>
+<tab name="C++">
+{{File
+  |name=pi.cxx
+  |lang="C++"
+  |contents=
+#include <iostream>
+#include <iomanip>
+const long long N=2000000000;
+const int vl=512;
+int main(int argc,char** argv) {
+  double pi = 0.0f;
+  long long i;
+  #pragma acc parallel vector_length(vl)
+  #pragma acc loop reduction(+:pi)
+  for (i = 0; i < N; i++) {
+    double t = double((i + 0.5) / N);
+    pi += 4.0/(1.0 + t * t);
+  }
+  std::cout << std::fixed;
+  std::cout << std::setprecision(10);
+  std::cout << "pi = " << pi/double(N) << std::endl;
    return 0;
 }