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Cpp #3

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Cpp #3

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264bbc3
type of problem
SssiiiSssiii Apr 11, 2022
86bae42
type of problem
SssiiiSssiii Apr 11, 2022
8b8a52c
Delete New Text Document.txt
SssiiiSssiii Apr 11, 2022
62e41e4
convert to CPP
SssiiiSssiii Apr 11, 2022
ecbdd2f
add type of problem
SssiiiSssiii Apr 12, 2022
4656962
Update first.cpp
SssiiiSssiii Apr 17, 2022
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Update first.cpp
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@SssiiiSssiii
SssiiiSssiii committed Apr 17, 2022
commit 46569628281d7896e8588f3109091d9af136e1e2
120 changes: 71 additions & 49 deletions firstSet ( Compiler problem )/first.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@
#include <cstring>
#include <algorithm>
#include <set>
#include <regex>
using namespace std;

int theNubmerOfRules;
Expand All @@ -20,9 +21,9 @@ string getTerminal(string currentRule, int stratFrom) {

if (isspace(currentRule[i]))
break;
terminal += currentRule[i];

terminal += currentRule[i];

}
return terminal;
}
Expand All @@ -42,9 +43,9 @@ string getNonTerminal(string currentRule, int stratFrom) {
}
string firstTerminal(string currentRule, string productionsRules[]) {
string firstSet = "";
char TerminalOrNonTerminal = currentRule[currentRule.find('>')+2];
char TerminalOrNonTerminal = currentRule[currentRule.find('>') + 2];
int IndexOfTerminalOrNonTerminal = currentRule.find('>') + 2;

if (!isupper(TerminalOrNonTerminal)) {
//to guarantee epsilon in the correct pos.
if (currentRule.back() != '$' && TerminalOrNonTerminal == '$') {
Expand All @@ -55,11 +56,11 @@ string firstTerminal(string currentRule, string productionsRules[]) {
return firstSet;
}
else {
string nonTerminal = getNonTerminal(currentRule, IndexOfTerminalOrNonTerminal);
string nonTerminal = getNonTerminal(currentRule, IndexOfTerminalOrNonTerminal);

for (int rule = 0; rule < theNubmerOfRules; rule++) {
string anotherNonTerminal = productionsRules[rule].substr(0, productionsRules[rule].find('-')-1);
string anotherNonTerminal = productionsRules[rule].substr(0, productionsRules[rule].find('-') - 1);

if (nonTerminal == anotherNonTerminal) {
currentRule = productionsRules[rule];
firstSet += firstTerminal(currentRule, productionsRules) + " ";
Expand All @@ -70,63 +71,84 @@ string firstTerminal(string currentRule, string productionsRules[]) {
}
return firstSet;
}
int countNetminalOrNonterminal(string rule, regex x) {

sregex_iterator currentMatch(rule.begin(), rule.end(), x);
sregex_iterator lm;
string out = "";

int c = 0;
while (currentMatch != lm) {
smatch match = *currentMatch;
++c;
currentMatch++;
}
return c;

}
set<string> getFirstSet(string NonTerminal) {

string currentRule;
set<string> firstSet;

bool hasEpsilon = true;

for (int j = 0; j < theNubmerOfRules; j++) {
string anotherNonTerminal = productionsRules[j].substr(0, productionsRules[j].find('-') - 1);
if ( NonTerminal == anotherNonTerminal) {
currentRule = productionsRules[j];
if (NonTerminal == anotherNonTerminal) {
currentRule = productionsRules[j];
regex b("[A-Za-z]+");

//No repetition
if (firstTerminal(currentRule, productionsRules).find("$") != firstTerminal(currentRule, productionsRules).npos && currentRule.size() != 6) {
char TerminalOrNonTerminal = currentRule[currentRule.find('>') + 2];
int IndexOfTerminalOrNonTerminal = currentRule.find('>') + 2;

for (int i = IndexOfTerminalOrNonTerminal; i < currentRule.size(); i++) {
if (!isspace(TerminalOrNonTerminal)) {
// cout << TerminalOrNonTerminal;
if (!isupper(TerminalOrNonTerminal)) {
if (firstSet.count(getTerminal(currentRule, i)) == 0)
firstSet.insert(getTerminal(currentRule, i));
hasEpsilon = false;
i += getTerminal(currentRule, i).size();
TerminalOrNonTerminal = currentRule[i];
}
else {
//to save from override
set<string> save = getFirstSet(getNonTerminal(currentRule, i));
firstSet.insert(save.begin(), save.end());

if (firstSet.count("$") != 0)
firstSet.erase("$");
else
hasEpsilon = false;

i += getNonTerminal(currentRule, i).size();
TerminalOrNonTerminal = currentRule[i + 1];

}
if (firstTerminal(currentRule, productionsRules).find("$") != firstTerminal(currentRule, productionsRules).npos && countNetminalOrNonterminal(currentRule, b) >= 3) {
cout << 55;
char TerminalOrNonTerminal = currentRule[currentRule.find('>') + 2];
int IndexOfTerminalOrNonTerminal = currentRule.find('>') + 2;
for (int i = IndexOfTerminalOrNonTerminal; i < currentRule.size(); i++) {
if (!isspace(TerminalOrNonTerminal)) {
if (!isupper(TerminalOrNonTerminal)) {
if (firstSet.count(getTerminal(currentRule, i)) == 0)
firstSet.insert(getTerminal(currentRule, i));
hasEpsilon = false;
i += getTerminal(currentRule, i).size();
TerminalOrNonTerminal = currentRule[i];

break;
}
else {
//to save from override
set<string> save = getFirstSet(getNonTerminal(currentRule, i));
firstSet.insert(save.begin(), save.end());
if (firstSet.count("$") != 0)
firstSet.erase("$");
else {

hasEpsilon = false;
break;
}
i += getNonTerminal(currentRule, i).size();
if (i < currentRule.size())
TerminalOrNonTerminal = currentRule[i + 1];


}

}
}

else {
hasEpsilon = false;
firstSet.insert(firstTerminal(currentRule, productionsRules));
}

}

else {

hasEpsilon = false;
firstSet.insert(firstTerminal(currentRule, productionsRules));
}

}
}

if (hasEpsilon)
firstSet.insert("$");

return firstSet;

}
Expand All @@ -136,12 +158,12 @@ int main()
cin.ignore();
//get productions rules
for (int i = 0; i < theNubmerOfRules; i++)
getline(cin,productionsRules[i]);
getline(cin, productionsRules[i]);

multiset<string>visited;
for (int rule = 0; rule < theNubmerOfRules; rule++) {
string currentRule = productionsRules[rule];
string nonTerminal = getNonTerminal(currentRule,0);
string nonTerminal = getNonTerminal(currentRule, 0);
visited.insert(nonTerminal);
set<string> firstSet;

Expand Down