This paper aims at exploring students' experiences when engaging in mathematical problem-solving through computational thinking and programming by a combination of theoretically derived insights and task-based activities. The main method used is a semi-structured interview with two undergraduate students who were presented with a mathematical task to solve while responding to questions about the mathematical solving process. The results reveal two students' opposite experiences. While one struggled to get acquainted with the task and the associated programming activity, the other was able to handle and solve the task using computational thinking (CT) and programming skills very easily. Conclusions are drawn from the students' experiences to promote mathematical problem-solving through computational thinking and programming in mathematics education at the undergraduate level.