利用后缀表达式计算中缀表达式的值

[{"title":"（ 22 个子文件 408KB ） 利用后缀表达式计算中缀表达式的值","children":[{"title":"calculator","children":[{"title":"calculator.h <span style='color:#111;'> 4.96KB </span>","children":null,"spread":false},{"title":"main.opt <span style='color:#111;'> 47.50KB </span>","children":null,"spread":false},{"title":"calculator.plg <span style='color:#111;'> 1.28KB </span>","children":null,"spread":false},{"title":"main.ncb <span style='color:#111;'> 33.00KB </span>","children":null,"spread":false},{"title":"utility.h <span style='color:#111;'> 6.86KB </span>","children":null,"spread":false},{"title":"main.dsw <span style='color:#111;'> 533B </span>","children":null,"spread":false},{"title":"calculator.ncb <span style='color:#111;'> 57.00KB </span>","children":null,"spread":false},{"title":"Debug","children":[{"title":"vc60.pdb <span style='color:#111;'> 68.00KB </span>","children":null,"spread":false},{"title":"main.ilk <span style='color:#111;'> 314.93KB </span>","children":null,"spread":false},{"title":"vc60.idb <span style='color:#111;'> 57.00KB </span>","children":null,"spread":false},{"title":"main.pdb <span style='color:#111;'> 505.00KB </span>","children":null,"spread":false},{"title":"main.obj <span style='color:#111;'> 46.37KB </span>","children":null,"spread":false},{"title":"main.pch <span style='color:#111;'> 435.13KB </span>","children":null,"spread":false},{"title":"main.exe <span style='color:#111;'> 248.07KB </span>","children":null,"spread":false}],"spread":true},{"title":"lk_stack.h <span style='color:#111;'> 4.92KB </span>","children":null,"spread":false},{"title":"main.plg <span style='color:#111;'> 738B </span>","children":null,"spread":false},{"title":"node.h <span style='color:#111;'> 640B </span>","children":null,"spread":false},{"title":"main.cpp <span style='color:#111;'> 669B </span>","children":null,"spread":false},{"title":"calculator.opt <span style='color:#111;'> 53.50KB </span>","children":null,"spread":false},{"title":"calculator.dsw <span style='color:#111;'> 545B </span>","children":null,"spread":false},{"title":"main.dsp <span style='color:#111;'> 3.30KB </span>","children":null,"spread":false},{"title":"calculator.dsp <span style='color:#111;'> 4.47KB </span>","children":null,"spread":false}],"spread":false}],"spread":true}]