华清远见嵌入式Linu长期就业班数据结构实验代码

#include <stdio.h> #include <stdlib.h> #define N 64 typedef struct _seqstack_ { int *data; int top; int size; }SeqStack; SeqStack *creat_stack(int size); int push_stack(SeqStack *stack, int value); int pop_stack(SeqStack *stack); int isempty(SeqStack *stack); int isfull(SeqStack *stack); int get_top(SeqStack *stack); int priority(int opt); int comput(int opd1, int opt, int opd2); int process_expression(SeqStack *operand, SeqStack *operator, int opt); int free_stack(SeqStack *stack); int main() { SeqStack *operand = NULL; SeqStack *operator = NULL; char buff[N]; char *p = buff; int sum = 0; operand = creat_stack(N); operator = creat_stack(N); gets(buff); while(*p != '\0') { if(*p >= '0' && *p <= '9') { sum = 0; while(*p >= '0' && *p <= '9') { sum *= 10; sum += *p - '0'; p ++; } push_stack(operand,sum); } else process_expression(operand, operator, *p ++); } while(!isempty(operator)) { int opd1,opd2,opt,result; opd2 = pop_stack(operand); opd1 = pop_stack(operand); opt = pop_stack(operator); result = comput(opd1,opt, opd2); push_stack(operand,result); } printf("%d\n",get_top(operand)); free_stack(operator); free_stack(operand); return 0; } int process_expression(SeqStack *operand, SeqStack *operator, int opt) { int opd1, opd2, opt1, result; if( !isempty(operator) && priority(opt) <= priority(get_top(operator)) ) { opd2 = pop_stack(operand); opd1 = pop_stack(operand); opt1 = pop_stack(operator); result = comput(opd1,opt1,opd2); push_stack(operand,result); } // else push_stack(operator,opt); } SeqStack *creat_stack(int size) { SeqStack *stack = NULL; stack = (SeqStack *)malloc(sizeof(SeqStack)); stack->data = (int *)malloc(sizeof(int) * size); stack->top = -1; stack->size = size; return stack; } int push_stack(SeqStack *stack, int value) { if(isfull(stack)) return -1; stack->data[++ stack->top] = value; return 0; } int pop_stack(SeqStack *stack) { if(isempty(stack)) return 0; return stack->data[stack->top --]; } int isempty(SeqStack *stack) { return stack->top < 0 ? 1 : 0; } int isfull(SeqStack *stack) { return stack->top >= stack->size - 1 ? 1 : 0; } int get_top(SeqStack *stack) { if(isempty(stack)) return 0; return stack->data[stack->top]; } int priority(int opt) { switch(opt) { case '+': case '-': return 1; case '*': case '/': return 2; default: return 0; } } int comput(int opd1, int opt, int opd2) { switch(opt) { case '+': return opd1 + opd2; case '-': return opd1 - opd2; case '*': return opd1 * opd2; case '/': return opd1 / opd2; default: return 0; } } int free_stack(SeqStack *stack) { free(stack->data); free(stack); return 0; }