commit a1019f66103857a1c258cdf944a8b18bae9f8e4b
author Sameer Agarwal <sameeragarwal@google.com> Sat Dec 12 15:02:15 2015 -0800
committer Keir Mierle <mierle@gmail.com> Thu Dec 17 20:21:42 2015 +0000
tree d1e8a93cb2866649788bdb340afc9cbf1b97b889
parent aaa0e3e4c804d00cf20211f755003dc9938776b3

Use std::adjacent_find instead of std::unique

When detecting duplicates, it is more efficient to use std::adjacent_find
than it is to use std::unique.

Change-Id: Ib6b4671c10848bb7dd10aa7a1baeffc8c9c825b5

internal/ceres/problem_impl.cc

diff --git a/internal/ceres/problem_impl.cc b/internal/ceres/problem_impl.cc
index 8547d5d..bb952be 100644
--- a/internal/ceres/problem_impl.cc
+++ b/internal/ceres/problem_impl.cc
@@ -249,10 +249,11 @@
     // Check for duplicate parameter blocks.
     vector<double*> sorted_parameter_blocks(parameter_blocks);
     sort(sorted_parameter_blocks.begin(), sorted_parameter_blocks.end());
-    vector<double*>::const_iterator duplicate_items =
-        unique(sorted_parameter_blocks.begin(),
-               sorted_parameter_blocks.end());
-    if (duplicate_items != sorted_parameter_blocks.end()) {
+    const bool has_duplicate_items =
+        (std::adjacent_find(sorted_parameter_blocks.begin(),
+                            sorted_parameter_blocks.end())
+         != sorted_parameter_blocks.end());
+    if has_duplicate_items {
       string blocks;
       for (int i = 0; i < parameter_blocks.size(); ++i) {
         blocks += StringPrintf(" %p ", parameter_blocks[i]);