Yahoo Chief Executive Officer Marissa Mayer said she apologized and did “feel really badly” for being late to a dinner with advertisers last week in Cannes, France, in her first public comments since facing criticism over the incident. Mayer said in an interview that she didn’t mean to slight attendees at the dinner hosted by Interpublic Group of Cos. at Cannes Lions, an advertising festival that drew Google Inc., AOL Inc., Microsoft Corp. and others. She said she was pleased overall with the more than 200 meetings that Yahoo had at Cannes…Mayer is responding after critics questioned her commitment to building relationships with advertisers following the Cannes event. The 39-year-old CEO kept guests waiting for about two hours at the dinner that was attended by top ad executives, according to people with knowledge of the matter, who asked not to be identified because the meal was private. Mayer later told guests she had overslept, said one of the people. Michael Roth, CEO of Interpublic Group, left before she arrived, the people said.