2026PKUCourseHW5: fix type conversion and file open check#7133

MiniYuanBot wants to merge 3 commits intodeepmodeling:developdeepmodeling/abacus-develop:developfrom

MiniYuanBot:feature/safe-type-conversion-and-file-checkMiniYuanBot/abacus-develop:feature/safe-type-conversion-and-file-checkCopy head branch name to clipboard