7. The flowchart editor of claim 3 wherein modifying the flowchart comprises: initializing a modified flowchart to comprise a begin node and an end node; setting a position between the begin and end nodes as a current position in the modified flowchart; setting the root node of the modified equivalent tree diagram as a current node in the modified flowchart; performing iteratively, while traversing the modified equivalent tree diagram, beginning with the current node until the current node equals a null node: fetching a next node in the equivalent tree diagram as the current node in depth first traversal; performing iteratively until the current node is not a leaf node: inserting a processing activity node corresponding to the current node into the current position; and moving the current position to a next insert position in that logic structure; generating a corresponding logic structure according to the execution type of the current node; inserting the logic structure into the current position; and moving the current position to the first insert position in said logic structure.
7. The flowchart editor of claim 3 wherein modifying the flowchart comprises: initializing a modified flowchart to comprise a begin node and an end node; setting a position between the begin and end nodes as a current position in the modified flowchart; setting the root node of the modified equivalent tree diagram as a current node in the modified flowchart; performing iteratively, while traversing the modified equivalent tree diagram, beginning with the current node until the current node equals a null node: fetching a next node in the equivalent tree diagram as the current node in depth first traversal; performing iteratively until the current node is not a leaf node: inserting a processing activity node corresponding to the current node into the current position; and moving the current position to a next insert position in that logic structure; generating a corresponding logic structure according to the execution type of the current node; inserting the logic structure into the current position; and moving the current position to the first insert position in said logic structure. 9. The flowchart editor of claim 7 wherein the computing device further performs: finding the at least one loop logic structure in the flowchart; cutting off each found loop logic structure; replacing the cut off found loop logic structure with a special marked node in the main processing flow; and storing the loop logic structure removed from the flowchart.