Add direct transformation to normal form

sat/simple.sat

@@ -1 +1,2 @@
- dfjsk&(dfjsk| !fjdsk| ((djask& ffadsfj)|fjskd))
+ a&(b| !c| ((!b& d)|e))
+ a&!b

src/expr.rs

@@ -1,4 +1,4 @@
-use crate::dpll::Index;
+use crate::{dpll::Index, mapping::Mapping, normal_form::NormalForm};
 use miette::{miette, Context, Result};
 use std::collections::HashMap;
 
@@ -243,6 +243,79 @@ impl<'s> Expr<'s> {
         }
     }
 
+    pub fn disjunctiveNormalForm2(self, mapping: &mut Mapping<'s>) -> NormalForm {
+        match self {
+            Expr::Literal(l) => {
+                let mut n = NormalForm::new();
+                n.add_clause(&[mapping.forward(l)]);
+                n
+            }
+            Expr::Not(e) => match *e {
+                Expr::Literal(l) => {
+                    let mut n = NormalForm::new();
+                    n.add_clause(&[-mapping.forward(l)]);
+                    n
+                }
+                Expr::Not(n) => n.disjunctiveNormalForm2(mapping),
+                Expr::And(v) => {
+                    let mut n = NormalForm::new();
+                    for e in v
+                        .into_iter()
+                        .map(|e| Expr::Not(Box::new(e)).disjunctiveNormalForm2(mapping))
+                    {
+                        for (s, _, _) in e.iter() {
+                            n.add_clause(s);
+                        }
+                    }
+                    n
+                }
+
+                Expr::Or(v) => Expr::And(v.into_iter().map(|e| Expr::Not(Box::new(e))).collect())
+                    .disjunctiveNormalForm2(mapping),
+            },
+            Expr::And(v) => {
+                let mut v: Vec<_> = v
+                    .into_iter()
+                    .map(|e| e.disjunctiveNormalForm2(mapping))
+                    .collect();
+
+                let mut n = v.pop().unwrap();
+
+                let mut scratch = Vec::new();
+
+                for on in v {
+                    let mut new_n = NormalForm::new();
+
+                    for (old_s, _, _) in n.iter() {
+                        for (new_s, _, _) in on.iter() {
+                            scratch.clear();
+                            scratch.extend_from_slice(old_s);
+                            scratch.extend_from_slice(new_s);
+                            scratch.sort();
+                            scratch.dedup();
+                            new_n.add_clause(&scratch);
+                        }
+                    }
+
+                    n = new_n;
+                }
+
+                n
+            }
+            Expr::Or(v) => {
+                let mut n = NormalForm::new();
+                for e in v {
+                    let on = e.disjunctiveNormalForm2(mapping);
+                    for (s, _, _) in on.iter() {
+                        n.add_clause(s);
+                    }
+                }
+
+                n
+            }
+        }
+    }
+
     pub fn conjunctiveNormalForm(self) -> Self {
         if let Expr::Or(v) = Expr::Not(Box::new(self)).disjunctiveNormalForm() {
             Expr::And(
@@ -275,6 +348,16 @@ impl<'s> Expr<'s> {
         }
     }
 
+    pub fn to_dpll_cnf_normal_form(self) -> (NormalForm, Mapping<'s>) {
+        let mut mapping = Mapping::new();
+
+        let mut cnf = Expr::Not(Box::new(self)).disjunctiveNormalForm2(&mut mapping);
+
+        cnf.negate();
+
+        (cnf, mapping)
+    }
+
     pub fn to_dpll_cnf(self) -> (Vec<Vec<Index>>, HashMap<&'s str, Index>) {
         let mut map = HashMap::new();
 

src/main.rs

@@ -3,12 +3,13 @@ use std::collections::HashMap;
 use clap::Parser;
 use dpll::dpll;
 use expr::{Expr, Tokanizer};
+use mapping::Mapping;
 use miette::{IntoDiagnostic, Result};
 use normal_form::NormalForm;
-mod dpll_normal_form;
-mod normal_form;
-
 mod dpll;
+mod dpll_normal_form;
+mod mapping;
+mod normal_form;
 
 mod expr;
 
@@ -28,39 +29,51 @@ fn main() -> Result<()> {
 
     // dbg!(&e);
     // dbg!(Expr::Not(Box::new(e.clone())).disjunctiveNormalForm());
-    // dbg!(e.clone().conjunctiveNormalForm());
 
-    let (cnf, map) = e.to_dpll_cnf();
+    let (cnf, map) = e.to_dpll_cnf_normal_form();
 
-    // dbg!(&cnf, &map);
-    println!("cnf clauses: {}", cnf.len());
+    println!("Normal form created.");
+    cnf.stats();
 
     let mut solution = Vec::new();
+    dbg!(crate::dpll_normal_form::dpll(&cnf, &mut solution));
 
-    dpll(&cnf, &mut solution);
+    // dbg!(&solution);
+    // dbg!(e.clone().conjunctiveNormalForm());
 
-    let inv_map: HashMap<_, _> = map.into_iter().map(|(k, v)| (v, k)).collect();
+    // let (cnf, map) = e.to_dpll_cnf();
 
-    dbg!(&solution);
-    // for i in solution {
-    //     if i > 0 {
-    //         println!("{}: true", inv_map[&i]);
-    //     } else {
-    //         println!("{}: false", inv_map[&i.abs()]);
-    //     }
-    // }
+    // dbg!(&cnf, &map);
+    // println!("cnf clauses: {}", cnf.len());
 
-    let mut nf = NormalForm::from_slices(&cnf);
+    // let mut solution = Vec::new();
+
+    // dpll(&cnf, &mut solution);
+
+    // dbg!(solution);
+
+    // let inv_map: HashMap<_, _> = map.into_iter().map(|(k, v)| (v, k)).collect();
+
+    // dbg!(&solution);
+    for i in solution {
+        if i > 0 {
+            println!("{}: true", map.backward(i));
+        } else {
+            println!("{}: false", map.backward(i.abs()));
+        }
+    }
+
+    // let mut nf = NormalForm::from_slices(&cnf);
     // dbg!(&nf);
 
     // nf.remove_literal(-1);
     // dbg!(&nf);
 
-    let mut s2 = Vec::new();
+    // let mut s2 = Vec::new();
 
-    dbg!(dpll_normal_form::dpll(&nf, &mut s2));
+    // dbg!(dpll_normal_form::dpll(&nf, &mut s2));
 
-    dbg!(s2 == solution);
+    // dbg!(s2 == solution);
 
     Ok(())
 }

src/mapping.rs

@@ -0,0 +1,32 @@
+use std::collections::HashMap;
+
+use crate::dpll::Index;
+
+pub struct Mapping<'s> {
+    forward: HashMap<&'s str, Index>,
+    backward: Vec<&'s str>,
+}
+
+impl<'s> Mapping<'s> {
+    pub fn new() -> Self {
+        Self {
+            forward: HashMap::new(),
+            backward: Vec::new(),
+        }
+    }
+
+    pub fn forward(&mut self, str: &'s str) -> Index {
+        if let Some(&i) = self.forward.get(str) {
+            i
+        } else {
+            let i = self.backward.len() as Index + 1;
+            self.forward.insert(str, i);
+            self.backward.push(str);
+            i
+        }
+    }
+
+    pub fn backward(&self, i: Index) -> &'s str {
+        self.backward[(i - 1) as usize]
+    }
+}

src/normal_form.rs

@@ -1,3 +1,5 @@
+use std::ops::Neg;
+
 use crate::dpll::Index;
 
 #[derive(Debug, Clone)]
@@ -66,7 +68,7 @@ impl NormalForm {
     pub fn add_clause(&mut self, s: &[Index]) {
         let len = s.len();
 
-        if self.data.len() < len {
+        if self.data.len() <= len {
             self.data.resize(len + 1, Vec::new());
         }
 
@@ -110,6 +112,25 @@ impl NormalForm {
     pub fn iter_len(&self, len: usize) -> NormalFormIteratorLen<'_> {
         NormalFormIteratorLen::new(self, len)
     }
+
+    pub fn negate(&mut self) {
+        for v in &mut self.data[1..] {
+            v.reverse();
+            for e in v {
+                *e = -*e;
+            }
+        }
+    }
+
+    pub fn stats(&self) {
+        println!("Normal form stats:");
+        let mut sum = 0;
+        for (i, v) in self.data.iter().enumerate() {
+            sum += v.len();
+            println!("{i:2}: {:15}", v.len() / usize::max(1, i));
+        }
+        println!("Total size: {}byte", sum * Index::BITS as usize / 8);
+    }
 }
 
 pub struct NormalFormIterator<'nf> {