Create Generate_3sat_instance.c

Signed-off-by: Josef Edwards <joed6834@colorado.edu>

Generate_3sat_instance.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+// Function to generate a random 3-SAT instance
+void generate_3sat_instance(int num_variables, int num_clauses, const char* filename) {
+    FILE *file = fopen(filename, "w");
+    if (!file) {
+        perror("Failed to open file for writing");
+        return;
+    }
+
+    // Write the header for the 3-SAT CNF instance
+    fprintf(file, "p cnf %d %d\n", num_variables, num_clauses);
+
+    // Randomly generate clauses
+    srand(time(0));  // Seed the random number generator
+
+    for (int i = 0; i < num_clauses; ++i) {
+        // Each clause consists of 3 literals, choose them randomly
+        for (int j = 0; j < 3; ++j) {
+            int var = rand() % num_variables + 1;  // Variable between 1 and num_variables
+            if (rand() % 2 == 0) {
+                var = -var;  // Randomly negate the variable
+            }
+            fprintf(file, "%d ", var);
+        }
+        fprintf(file, "0\n");  // End of clause
+    }
+
+    fclose(file);
+    printf("Generated random 3-SAT instance: %s\n", filename);
+}
+
+int main() {
+    int num_variables = 50;  // Number of variables
+    int num_clauses = 150;   // Number of clauses
+    const char* filename = "3sat_instance.cnf";  // Output file name
+    generate_3sat_instance(num_variables, num_clauses, filename);  // Generate instance
+    return 0;
+}