fix: Remove mod from X subtrahend in dff

The modular operation is likely incorrect in this case.
Removig it.

src/utils/dff.rs

@@ -11,29 +11,28 @@ pub struct Factors {
     pub degree: u32,
 }
 
-pub fn ddf(f: Polynomial) -> Vec<(Polynomial, usize)> {
+pub fn ddf(f: Polynomial) -> Vec<(Polynomial, u128)> {
     let q = BigUint::pow(&BigUint::from_u8(2).unwrap(), 128);
     eprintln!("q: {:?}", q);
 
-    let mut z: Vec<(Polynomial, usize)> = vec![];
-    let mut d: u32 = 1;
+    let mut z: Vec<(Polynomial, u128)> = vec![];
+    let mut d: u128 = 1;
     let mut f_star = f.clone();
 
     let one_cmp = Polynomial::one();
     while f_star.degree() >= (2 * d) as usize {
-        let h = Polynomial::x().bpow_mod(q.clone().pow(d), f_star.clone())
-            + Polynomial::x().div(&f_star).1;
+        let h = Polynomial::x().bpow_mod(q.clone().pow(d), f_star.clone()) + Polynomial::x();
 
         let g = gcd(&h, &f_star);
         if g != one_cmp {
-            z.push((g.clone(), d as usize));
+            z.push((g.clone(), d));
             f_star = f_star.div(&g).0;
         }
 
         d += 1;
     }
     if f_star != one_cmp {
-        z.push((f_star.clone(), f_star.degree()));
+        z.push((f_star.clone(), f_star.degree() as u128));
     } else if z.len() == 0 {
         z.push((f.clone(), 1));
     }

src/utils/sff.rs

@@ -10,14 +10,14 @@ use super::poly::Polynomial;
 #[derive(Debug, Serialize, Deserialize)]
 pub struct Factors {
     pub factor: Vec<String>,
-    pub exponent: u32,
+    pub exponent: u128,
 }
 
-pub fn sff(mut f: Polynomial) -> Vec<(Polynomial, u32)> {
+pub fn sff(mut f: Polynomial) -> Vec<(Polynomial, u128)> {
     let mut c = gcd(&f, &f.clone().diff());
     f = f.div(&c).0;
-    let mut z: Vec<(Polynomial, u32)> = vec![];
-    let mut e: u32 = 1;
+    let mut z: Vec<(Polynomial, u128)> = vec![];
+    let mut e: u128 = 1;
 
     let one_element = Polynomial::new(vec![FieldElement::new(
         polynomial_2_block(vec![0], "gcm").unwrap(),

test_json/sandbox.json

@@ -1,24 +1,15 @@
 {
   "testcases": {
     "sandbox": {
-      "action": "gfpoly_factor_sff",
+      "action": "gfpoly_factor_ddf",
       "arguments": {
         "F": [
-          "vL77UwAAAAAAAAAAAAAAAA==",
-          "mEHchYAAAAAAAAAAAAAAAA==",
-          "9WJa0MAAAAAAAAAAAAAAAA==",
-          "akHfwWAAAAAAAAAAAAAAAA==",
-          "E12o/QAAAAAAAAAAAAAAAA==",
-          "vKJ/FgAAAAAAAAAAAAAAAA==",
-          "yctWwAAAAAAAAAAAAAAAAA==",
-          "c1BXYAAAAAAAAAAAAAAAAA==",
-          "o0AtAAAAAAAAAAAAAAAAAA==",
-          "AbP2AAAAAAAAAAAAAAAAAA==",
-          "k2YAAAAAAAAAAAAAAAAAAA==",
-          "vBYAAAAAAAAAAAAAAAAAAA==",
-          "dSAAAAAAAAAAAAAAAAAAAA==",
-          "69gAAAAAAAAAAAAAAAAAAA==",
-          "VkAAAAAAAAAAAAAAAAAAAA==",
+          "tpkgAAAAAAAAAAAAAAAAAA==",
+          "m6MQAAAAAAAAAAAAAAAAAA==",
+          "8roAAAAAAAAAAAAAAAAAAA==",
+          "3dUAAAAAAAAAAAAAAAAAAA==",
+          "FwAAAAAAAAAAAAAAAAAAAA==",
+          "/kAAAAAAAAAAAAAAAAAAAA==",
           "a4AAAAAAAAAAAAAAAAAAAA==",
           "gAAAAAAAAAAAAAAAAAAAAA=="
         ]