词法分析

词法分析

代码实现

#include<bits/stdc++.h>
#define int long long
#define PII pair<int , int>
using namespace std;
const int N = 1e6 + 10;
int n , k = 1 , x1 = 0 , x0 = 0;
int mid = 1e9 + 7;
map<string , int>mp;void matt(){   string s;while(getline(cin , s)){stringstream t(s);string ss;while (t >> ss){n = ss.size();int i = 0;string ssr = "";// cout << ss << '\n';while (i < n){if(i != n - 1 && ss[i] == '*' && ss[i + 1] == '/') {x0 = 0 ;i += 2;continue;}if(x0) {i ++ ; continue ;}if(isalpha(ss[i]) || ss[i] == '_' || isdigit(ss[i])){ssr += ss[i];}else{if(i != n - 1 && ss[i] == '.' && isdigit(ss[i - 1]) && isdigit(ss[i + 1])) {ssr += '.';i++;continue;}if(ssr != ""){if(!mp[ssr]){mp[ssr] = k++;}cout << ssr << '\n';ssr = "";}if(i != n - 1 && ss[i] == '/' && ss[i + 1] == '/') {x1 = 1 ;break;}else if(i != n - 1 && ss[i] == '/' && ss[i + 1] == '*') {x0 = 1 ;i++;continue;}else if(i != n - 1 && ss[i] == '+' && ss[i + 1] == '+'){cout << "++\n";if(!mp["++"]){mp["++"] = k++;}i++;}else if(i != n - 1 && ss[i] == '-' && ss[i + 1] == '-'){cout << "--\n";if(!mp["--"]){mp["--"] = k++;}i++;}else if(i != n - 1 && ss[i] == '=' && ss[i + 1] == '='){cout << "==\n";if(!mp["=="]){mp["=="] = k++;}i++;}else if(i != n - 1 && ss[i] == '!' && ss[i + 1] == '='){cout << "!=\n";if(!mp["!="]){mp["!="] = k++;}i++;}else if(i != n - 1 && ss[i] == '+' && ss[i + 1] == '='){cout << "+=\n";if(!mp["+="]){mp["+="] = k++;}i++;}else if(i != n - 1 && ss[i] == '-' && ss[i + 1] == '='){cout << "-=\n";if(!mp["-="]){mp["-="] = k++;}i++;}else if(i != n - 1 && ss[i] == '*' && ss[i + 1] == '='){cout << "*=\n";if(!mp["*="]){mp["*="] = k++;}i++;}else if(i != n - 1 && ss[i] == '/' && ss[i + 1] == '='){cout << "/=\n";if(!mp["/="]){mp["/="] = k++;}i++;}else if(i != n - 1 && ss[i] == '&' && ss[i + 1] == '&'){cout << "&&\n";if(!mp["&&"]){mp["&&"] = k++;}i++;}else if(i != n - 1 && ss[i] == '|' && ss[i + 1] == '|'){cout << "||\n";if(!mp["||"]){mp["||"] = k++;}i++;}else if(i != n - 1 && ss[i] == '<' && ss[i + 1] == '<'){cout << "<<\n";if(!mp["<<"]){mp["<<"] = k++;}i++;}else if(i != n - 1 && ss[i] == '>' && ss[i + 1] == '>'){cout << ">>\n";if(!mp[">>"]){mp[">>"] = k++;}i++;}else if(i != n - 1 && ss[i] == '\\' && ss[i + 1] == 'n'){cout << "\\n" << '\n';if(!mp["\\n"]){mp["\\n"] = k++;}i++;}else if(i != n - 1 && ss[i] == '%' && ss[i + 1] == 'd'){cout << "%d\n";if(!mp["%d"]){mp["%d"] = k++;}i++;}else if(i != n - 1 && ss[i] == '%' && ss[i + 1] == 'f'){cout << "%f\n";if(!mp["%f"]){mp["%f"] = k++;}i++;}else if(i != n - 1 && ss[i] == '%' && ss[i + 1] == 'c'){cout << "%c\n";if(!mp["%c"]){mp["%c"] = k++;}i++;}else {cout << ss[i] << '\n';ssr += ss[i];if(!mp[ssr]){mp[ssr] = k++;}ssr = "";}}i++;}if(ssr != "") {cout << ssr << '\n';if(!mp[ssr]) mp[ssr] = k++;}if(x1) {x1 = 0; break;}}}cout << '\n' << '\n';for(auto x : mp){cout << x.first << ' ' << x.second << '\n';}
}signed main(){ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);int T = 1;// cin >> T;while (T--){matt();}return 0;
}

输入内容

int main(){// ios::sync_with_stdio(false);// cin.tie(0);// cout.tie(0);int T = 1;cin >> T;while (T--){int n , m;cin >> n;scanf("%d" , &m);int ans = 0;double x = 1.2;while (n){if(n <= 2) n = 0 , ans++;else if( n % 2 == 0) n /= 2 , ans++;else n-- , ans++;}cout << ans << '\n';}return 0;
}

输出内容

int
main
(
)
{
int
T
=
1
;
cin
>>
T
;
while
(
T
--
)
{
int
n
,
m
;
cin
>>
n
;
scanf
(
"
%d
"
,
&
m
)
;
int
ans
=
0
;
double
x
=
1.2
;
while
(
n
)
{
if
(
n
<
=
2
)
n
=
0
,
ans
++
;
else
if
(
n
%
2
==
0
)
n
/=
2
,
ans
++
;
else
n
--
,
ans
++
;
}
cout
<<
ans
<<
'
\n
'
;
}
return
0
;
}" 18
% 31
%d 19
& 20
' 37
( 3
) 4
++ 29
, 15
-- 13
/= 33
0 22
1 8
1.2 25
2 28
; 9
< 27
<< 36
= 7
== 32
>> 11
T 6
\n 38
ans 21
cin 10
cout 35
double 23
else 30
if 26
int 1
m 16
main 2
n 14
return 39
scanf 17
while 12
x 24
{ 5
} 34