c++逆波蘭式計算表達式

#include<stdio.h>
#include<string.h>
#include<stack>
#include<map>
using namespace std;
map<char,int> OP_PRI;
char ep[105];
char he[105];

void init(){
    OP_PRI['('] = 9999;
    OP_PRI[')'] = -1;
    OP_PRI['#'] = 0;
    OP_PRI['+'] = 1;
    OP_PRI['-'] = 1;
    OP_PRI['*'] = 2;
    OP_PRI['/'] = 2;
}

void getHz(){
    int len = strlen(ep);
    stack<char> op;
    stack<char> hz;
    op.push('#');
    for(int i = 0;i < len;i++){
        if(ep[i] >= '0' && ep[i] <= '9'){
            hz.push(ep[i]);
        }else{
            if(ep[i] == ')'){
                while(op.top() != '('){
                    hz.push(op.top());
                    op.pop();
                }
                op.pop();
                continue;
            }

            while(op.top() != '(' && OP_PRI[ep[i]] < OP_PRI[op.top()]){
                hz.push(op.top());
                op.pop();
            }
            op.push(ep[i]);
        }
    }
    stack<char> tmp;
    while(!hz.empty()){
        tmp.push(hz.top());
        hz.pop();
    }
    int cnt = 0;
    while(!tmp.empty()){
        he[cnt++] = tmp.top();
        tmp.pop();
    }
    while(!op.empty()){
        he[cnt++] = op.top();
        op.pop();
    }
    he[cnt-1] = '\0';
}

int cal(){
    stack<int> data;
    for(int i = 0;he[i] != '\0';i++){
        if(he[i] >= '0' && he[i] <= '9'){
            data.push(he[i]-'0');
        }else{
            int b = data.top();
            data.pop();
            int a = data.top();
            data.pop();
            if(he[i] == '+'){
                data.push(a+b);
            }else if(he[i] == '-'){
                data.push(a-b);
            }else if(he[i] == '/'){
                data.push(a/b);
            }else if(he[i] == '*'){
                data.push(a*b);
            }
        }
    }
    return data.top();
}
int main(){
    init();
    scanf("%s",ep);
    getHz();
    printf("%s  --->   %s\n",ep,he);
    printf("=%d\n",cal());
    return 0;
}