Data structure written test: prefix expression | suffix expression

Here I give an infix expression: a+b*c-(d+e) The first step: the operator's priority to all operating units in parentheses: the formula becomes: ((A + (B*C))-(d+e)) The second step: the conversion prefix and suffix expression prefix: Move the operation symbol to the corresponding parenthesis before it becomes:- (+ (A * (BC)) + (DE)) Remove the brackets:-+a*bc+de prefix suffix: Move the operation symbol to the corresponding parenthesis after it becomes: ((A (BC) *) + (DE) +)-The parentheses are removed: abc*+de+-suffix appears so easy~

Data structure written test: prefix expression | suffix expression