more graph cleaning; add floating point version of min cost flow

ortools/graph/BUILD.bazel

@@ -565,6 +565,35 @@ cc_test(
     ],
 )
 
+# Min Cost Flow with floating point flow.
+cc_library(
+    name = "fp_min_cost_flow",
+    srcs = ["fp_min_cost_flow.cc"],
+    hdrs = ["fp_min_cost_flow.h"],
+    deps = [
+        ":min_cost_flow",
+        "//ortools/util:fp_roundtrip_conv",
+        "//ortools/util:saturated_arithmetic",
+        "@com_google_absl//absl/algorithm:container",
+        "@com_google_absl//absl/log",
+        "@com_google_absl//absl/log:check",
+    ],
+)
+
+# cc_test(
+#     name = "fp_min_cost_flow_test",
+#     srcs = ["fp_min_cost_flow_test.cc"],
+#     deps = [
+#         ":fp_min_cost_flow",
+#         ":min_cost_flow",
+#         "//absl/base:no_destructor",
+#         "//ortools/base:gmock_main",
+#         "//ortools/util:fp_roundtrip_conv",
+#         "@com_google_absl//absl/base:log_severity",
+#         "@com_google_absl//absl/strings",
+#     ],
+# )
+
 # Flow-problem solver
 cc_binary(
     name = "solve_flow_model",