Day 15 part 1 solution

15/15-1.c

@@ -0,0 +1,83 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdbool.h>
+
+#define PART_2
+
+#define SPACE_SIZE 10
+
+typedef struct
+{
+    int risk;
+    int min_risk_path;
+    bool explored;
+} CELL;
+
+typedef CELL **SPACE;
+
+#define VALID_POSITION(x, y) (x < SPACE_SIZE && x >= 0 && y < SPACE_SIZE && y >= 0)
+#define END(x, y) (x == SPACE_SIZE - 1 && y == SPACE_SIZE - 1)
+
+void print_space(SPACE space)
+{
+    for (size_t i = 0; i < SPACE_SIZE; i++)
+    {
+        for (size_t j = 0; j < SPACE_SIZE; j++)
+            // printf("%d(%c,%d)", space[i][j].risk, space[i][j].explored ? '*' : '.', space[i][j].min_risk_path);
+            printf("%d(%d)", space[i][j].risk, space[i][j].min_risk_path);
+        putchar('\n');
+    }
+    putchar('\n');
+}
+
+void node_risk(SPACE space, int x, int y, int risk)
+{
+    if (!VALID_POSITION(x, y))
+        return;
+    risk += space[x][y].risk;
+    if (risk < space[x][y].min_risk_path)
+        space[x][y].min_risk_path = risk;
+}
+
+int main(int argc, char const *argv[])
+{
+    FILE *p_file = fopen("input", "r");
+    SPACE space = calloc(SPACE_SIZE, sizeof(CELL *));
+    for (size_t i = 0; i < SPACE_SIZE; i++)
+    {
+        space[i] = calloc(SPACE_SIZE, sizeof(CELL));
+        char buf[SPACE_SIZE + 2];
+        fgets(buf, sizeof buf, p_file);
+        for (size_t j = 0; j < SPACE_SIZE; j++)
+        {
+            space[i][j].risk = buf[j] - '0';
+            space[i][j].explored = false;
+            space[i][j].min_risk_path = __INT_MAX__;
+        }
+    }
+
+    space[0][0].min_risk_path = 0;
+    for (size_t i = 0; i < 500; i++) // What the fuck? Brute forced it
+    {
+        for (size_t c = 0; c < SPACE_SIZE * 2; c++)
+        {
+            for (size_t x = 0; x <= c; x++)
+            {
+                int y = c - x;
+                if (VALID_POSITION(x, y))
+                {
+                    space[x][y].explored = true;
+                    node_risk(space, x + 1, y, space[x][y].min_risk_path);
+                    node_risk(space, x, y + 1, space[x][y].min_risk_path);
+                    node_risk(space, x - 1, y, space[x][y].min_risk_path);
+                    node_risk(space, x, y - 1, space[x][y].min_risk_path);
+                }
+            }
+        }
+    }
+    // print_space(space);
+
+    printf("Minimum risk %d\n", space[SPACE_SIZE - 1][SPACE_SIZE - 1].min_risk_path);
+
+    return 0;
+}