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 withdigit那里判断小数或者科学计数法的，但是现在只考虑整数就改掉了

#include <iostream>
#include<stdlib.h>
#include <cstring>
#include <ctype.h>
#include<cstdlib>
using namespace std;

class TOKEN{
public:
    int typenum = 0;
    // string type = "";
    string symb = "";
    int value = 0;
    void print(){
        if (typenum == -1)
            return;
        // printf("<%d,\t%s>\n", typenum, symb);
        if (typenum == 111 || typenum == -2){
            cout << '<' << typenum << ",\t" << symb << '>' << endl;
        }
        else if(typenum == 100){
            cout << '<' << typenum << ",\t" << value << '>' << endl;
        }
        else {
            cout << '<' << typenum << ",\t->" << endl;
        }
    }
};

int judge(char a){ //judeg symbol
    if (isdigit(a)){
        return 1;
    }
    else  if (isalnum(a)){
        return 2;
    }
    return 0;
}
int withdigit(char a){ // follow num
    if (isdigit(a)){
        return 1;
    }
    if (a == '.'){
        return 0;
    }
    if (a == 'e' || a == 'E'){
        return 0;
    }
    return 0;
}
// int find(char a, TOKEN &t){
//     switch (a)
//     {
//     case '+':
//         t.typenum = 41;
//         t.symb = "+";
//         break;

//     default:
//         t.typenum = -2;
//         t.symb = "?";
//         break;
//     }
// }
void selfjudge(TOKEN &a){
    if (a.symb == "int"){
        a.typenum = 5;
    }
    else if (a.symb == "else"){
        a.typenum = 15;
    }
    else if (a.symb == "if"){
        a.typenum = 17;
    }
    else if (a.symb == "while"){
        a.typenum = 20;
    }
}
TOKEN lexer(char temp){
    TOKEN target;
    int flag = 1;
    char next;
    if (isdigit(temp)){ //num
        flag = 0;
        target.symb += temp;
        while (1){
            temp = getchar();
            if (!withdigit(temp)){
                flag = 1;
                break;
            }
            target.symb += temp;
        }
        if (flag == 1){
            ungetc(temp, stdin);
        }
        target.typenum = 100;
        target.value = atoi(target.symb.c_str());
    }
    else if (judge(temp) == 2){ // all words
        flag = 0;
        target.symb += temp;
        while (1){
            temp = getchar();
            if (judge(temp) == 0){
                flag = 1;
                break;
            }
            target.symb += temp;
        }
        if (flag == 1){
            ungetc(temp, stdin);
        }
        target.typenum = 111;
    }
    else if (temp == ' ' || temp == '\n'){ // blank
        target.typenum = -1;
    }
    else{ // not word
        // find(temp, target);
            switch (temp)
        {
        case '+':
            next = getchar();
            if (next == '+'){
                target.typenum = 56;
                target.symb = "++";
                break;
            }
            ungetc(next, stdin);
            target.typenum = 41;
            target.symb = "+";
            break;
        case '-':
            next = getchar();
            if (next == '-'){
                target.typenum = 57;
                target.symb = "--";
                break;
            }
            ungetc(next, stdin);
            target.typenum = 42;
            target.symb = "-";
            break;
        case '*':
            target.typenum = 43;
            target.symb = "*";
            break;
        case '/':
            target.typenum = 44;
            target.symb = "/";
            break;
        case '%':
            target.typenum = 45;
            target.symb = "%";
            break;
        case '>':
            next = getchar();
            if (next == '='){
                target.typenum = 48;
                target.symb = ">=";
                break;
            }
            ungetc(next, stdin);
            target.typenum = 47;
            target.symb = ">";
            break;
        case '<':
            next = getchar();
            if (next == '='){
                target.typenum = 50;
                target.symb = "<=";
                break;
            }
            ungetc(next, stdin);
            target.typenum = 49;
            target.symb = "<";
            break;
        case '=':
            next = getchar();
            if (next == '='){
                target.typenum = 50;
                target.symb = "==";
                break;
            }
            ungetc(next, stdin);
            target.typenum = 44;
            target.symb = "=";
            break;
        case '!':
            next = getchar();
            if (next == '='){
                target.typenum = 52;
                target.symb = "!=";
                break;
            }
            ungetc(next, stdin);
            target.typenum = 55;
            target.symb = "!";
            break;
        case '&':
            next = getchar();
            if (next == '&'){
                target.typenum = 53;
                target.symb = "&&";
                break;
            }
            ungetc(next, stdin);
            target.typenum = -2;
            target.symb = "err";
            break;
        case '|':
            next = getchar();
            if (next == '|'){
                target.typenum = 54;
                target.symb = "||";
                break;
            }
            ungetc(next, stdin);
            target.typenum = -2;
            target.symb = "err";
            break;
        case '(':
            target.typenum = 81;
            target.symb = ")";
            break;
        case ')':
            target.typenum = 82;
            target.symb = ")";
            break;
        case ';':
            target.typenum = 84;
            target.symb = ";";
            break;
        case '{':
            target.typenum = 86;
            target.symb = "{";
            break;
        case '}':
            target.typenum = 87;
            target.symb = "}";
            break;
        case '[':
            target.typenum = 88;
            target.symb = "[";
            break;
        case ']':
            target.typenum = 89;
            target.symb = "]";
            break;

        default:
            target.typenum = -2;
            target.symb = "err";
            break;
        }
    }
    selfjudge(target);
    return target;
}

int main(){
    char a;
    while (a=getchar())
    {
        if (a != EOF) {
            TOKEN token = lexer(a);
            token.print();
        }
    }
    return 1;
}