Add missing <algorithm> headers.

Thanks to kea@google.com for reporting this.

Change-Id: I9bde5823e9ea89451f476694c9b860080dffdf17

internal/ceres/coordinate_descent_minimizer.cc

diff --git a/internal/ceres/coordinate_descent_minimizer.cc b/internal/ceres/coordinate_descent_minimizer.cc
index 087f01f..6f20f20 100644
--- a/internal/ceres/coordinate_descent_minimizer.cc
+++ b/internal/ceres/coordinate_descent_minimizer.cc
@@ -34,6 +34,7 @@
 #include "ceres/parallel_for.h"
 #endif
 
+#include <algorithm>
 #include <iterator>
 #include <memory>
 #include <numeric>

internal/ceres/dogleg_strategy.cc

diff --git a/internal/ceres/dogleg_strategy.cc b/internal/ceres/dogleg_strategy.cc
index 839e181..b3c52b9 100644
--- a/internal/ceres/dogleg_strategy.cc
+++ b/internal/ceres/dogleg_strategy.cc
@@ -30,7 +30,9 @@
 
 #include "ceres/dogleg_strategy.h"
 
+#include <algorithm>
 #include <cmath>
+
 #include "Eigen/Dense"
 #include "ceres/array_utils.h"
 #include "ceres/internal/eigen.h"

internal/ceres/levenberg_marquardt_strategy.cc

diff --git a/internal/ceres/levenberg_marquardt_strategy.cc b/internal/ceres/levenberg_marquardt_strategy.cc
index e983380..8565800 100644
--- a/internal/ceres/levenberg_marquardt_strategy.cc
+++ b/internal/ceres/levenberg_marquardt_strategy.cc
@@ -30,7 +30,9 @@
 
 #include "ceres/levenberg_marquardt_strategy.h"
 
+#include <algorithm>
 #include <cmath>
+
 #include "Eigen/Core"
 #include "ceres/array_utils.h"
 #include "ceres/internal/eigen.h"

internal/ceres/line_search.cc

diff --git a/internal/ceres/line_search.cc b/internal/ceres/line_search.cc
index 1a88ebb..86302a9 100644
--- a/internal/ceres/line_search.cc
+++ b/internal/ceres/line_search.cc
@@ -30,6 +30,7 @@
 
 #include "ceres/line_search.h"
 
+#include <algorithm>
 #include <iomanip>
 #include <iostream>  // NOLINT
 

internal/ceres/loss_function.cc

diff --git a/internal/ceres/loss_function.cc b/internal/ceres/loss_function.cc
index eb50267..50612f5 100644
--- a/internal/ceres/loss_function.cc
+++ b/internal/ceres/loss_function.cc
@@ -32,6 +32,7 @@
 
 #include "ceres/loss_function.h"
 
+#include <algorithm>
 #include <cmath>
 #include <cstddef>
 #include <limits>

internal/ceres/program.cc

diff --git a/internal/ceres/program.cc b/internal/ceres/program.cc
index 31b5d1a..994c5aa 100644
--- a/internal/ceres/program.cc
+++ b/internal/ceres/program.cc
@@ -30,6 +30,7 @@
 
 #include "ceres/program.h"
 
+#include <algorithm>
 #include <map>
 #include <memory>
 #include <vector>