中缀转后缀

#include<stdio.h>

int top=0;
char stack[100];
void push(char x)
{
stack[top++]=x;
}
void pop()
{
printf("%c",stack[--top]);
}
void inToPost(char *a)
{
int i;
for(i=0;a[i]!='\0';i++){
if(a[i]>='a'&&a[i]<='z')
printf("%c",a[i]);
else if(a[i]=='+'||a[i]=='-'){
while(top!=0&&stack[top-1]!='('){
pop();
}
push(a[i]);
}
else if(a[i]=='*'||a[i]=='/'){
push(a[i]);
}
else if(a[i]=='('){
push(a[i]);
}
else if(a[i]==')'){
while(stack[top-1]!='('){
pop();
}
top--;
}
}
while(top!=0)pop();
}

int main()
{
char a[100];
gets(a);
inToPost(a);
return 0;
}