{"task_id":"reverse-string","prompt":"Implement reverse_string(text), returning the characters in reverse order.","entry_point":"reverse_string","tests":[{"args":["hello"],"expected":"olleh"},{"args":[""],"expected":""},{"args":["a b"],"expected":"b a"}]}
{"task_id":"valid-parentheses","prompt":"Implement valid_parentheses(text). The input contains only ()[]{}. Return whether every bracket is correctly matched and nested.","entry_point":"valid_parentheses","tests":[{"args":["()[]{}"],"expected":true},{"args":["([{}])"],"expected":true},{"args":["(]"],"expected":false},{"args":["([)]"],"expected":false}]}
{"task_id":"binary-search","prompt":"Implement binary_search(values, target) for an ascending list of distinct integers. Return the target index or -1 when absent.","entry_point":"binary_search","tests":[{"args":[[1,3,5,7],5],"expected":2},{"args":[[1,3,5,7],2],"expected":-1},{"args":[[],4],"expected":-1}]}
{"task_id":"max-subarray","prompt":"Implement max_subarray(values), returning the maximum sum of a non-empty contiguous subarray.","entry_point":"max_subarray","tests":[{"args":[[-2,1,-3,4,-1,2,1,-5,4]],"expected":6},{"args":[[-5,-2,-8]],"expected":-2},{"args":[[7]],"expected":7}]}