有关栈API详情參看我的还有一篇博文:
遍历后缀表达式中的数字和符号
对于数字:进栈 对于符号: 从栈中弹出右操作数 从栈中弹出左操作数 依据符号进行运算 将运算结果压入栈中 遍历结束:栈中的唯一数字为计算结果#includeproject文件详情:#include "LinkStack.h"int isNumber3(char c){ return ('0' <= c) && (c <= '9');}int isOperator3(char c){ return (c == '+') || (c == '-') || (c == '*') || (c == '/');}int value(char c){ return (c - '0');}int express(int left, int right, char op){ int ret = 0; switch (op) { case '+': ret = left + right; break; case '-': ret = left - right; break; case '*': ret = left * right; break; case '/': ret = left / right; break; default: break; } return ret;}int compute(const char* exp){ LinkStack* stack = LinkStack_Create(); int ret = 0; int i = 0; while (exp[i] != '\0') { if (isNumber3(exp[i])) { LinkStack_Push(stack, (void*)value(exp[i])); } else if (isOperator3(exp[i])) { int right = (int)LinkStack_Pop(stack); int left = (int)LinkStack_Pop(stack); int result = express(left, right, exp[i]); LinkStack_Push(stack, (void*)result); } else { printf("Invalid expression!"); break; } i++; } if ((LinkStack_Size(stack) == 1) && (exp[i] == '\0')) { ret = (int)LinkStack_Pop(stack); } else { printf("Invalid expression!"); } LinkStack_Destroy(stack); return ret;}int main(){ printf("8 + (3 - 1) * 5 = %d\n", compute("831-5*+")); return 0;}