X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/d47debaeffa6807956ee9cc7da90759efe49beda..6760cb07d6b57be16928d95339d71e57c4e24f36:/src/smpi/sample/reduce.c

diff --git a/src/smpi/sample/reduce.c b/src/smpi/sample/reduce.c
index 9fc0be2483..d939385bba 100644
--- a/src/smpi/sample/reduce.c
+++ b/src/smpi/sample/reduce.c
@@ -1,31 +1,33 @@
+/* Copyright (c) 2007, 2009, 2010. The SimGrid Team.
+ * All rights reserved.                                                     */
+
+/* This program is free software; you can redistribute it and/or modify it
+  * under the terms of the license (GNU LGPL) which comes with this package. */
+
 #include <stdio.h>
-#include <stdlib.h>
 #include <mpi.h>
 
-int main(int argc, char *argv[]) {
-  int rank, size;
-  int i;
-  int *sendbuf, *recvbuf;
+int main (int argc, char **argv) {
+  int size, rank;
+  int root=0;
+  int value = 1;
+  int sum=-99;
+
+  double start_timer;
+
+
   MPI_Init(&argc, &argv);
-  MPI_Comm_rank(MPI_COMM_WORLD, &rank);
   MPI_Comm_size(MPI_COMM_WORLD, &size);
-  sendbuf = malloc(sizeof(int) * size);
-  recvbuf = malloc(sizeof(int) * size);
-  for (i = 0; i < size; i++) {
-    sendbuf[i] = 0;
-    recvbuf[i] = 0;
-  }
-  sendbuf[rank] = rank + 1;
-  MPI_Reduce(sendbuf, recvbuf, size, MPI_INT, MPI_SUM, 0, MPI_COMM_WORLD);
-  if (0 == rank) {
-    printf("nodes: ", rank);
-    for (i = 0; i < size; i++) {
-      printf("%d ", recvbuf[i]);
-    }
-    printf("\n");
+  MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+
+  start_timer = MPI_Wtime();
+
+  printf("rank %d has value %d\n", rank, value);
+  MPI_Reduce(&value, &sum, 1, MPI_INT, MPI_SUM, root, MPI_COMM_WORLD);
+  if ( rank == root) {
+          printf("On root: sum=%d\n",sum);
+	    printf("Elapsed time=%lf s\n", MPI_Wtime()-start_timer);
   }
-  free(sendbuf);
-  free(recvbuf);
   MPI_Finalize();
   return 0;
 }