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+// 1824. Minimum Sideway Jumps
+#include "leetcode.h"
+
+/*
+ * there is a 3 lane road of length 'n' that consists of 'n + 1' points labeled
+ * from 0 to 'n'. a frog starts at point 0 in the second lane and wants to jump
+ * to point 'n'. however there could be obstacles along the way. you are given
+ * an array 'obstacles' of length 'n + 1' where each 'obstacles[i]' (ranging
+ * from 0 to 3) describes an obstacle on the lane 'obstacles[i]' at point 'i'.
+ * if 'obstacles[i] == 0' there are no obstacles at point 'i'. there will be at
+ * most one obstacles in the 3 lanes at each point. the frog can only travel
+ * from point 'i' to point 'i + 1' on the same lane if there is not an obstacle
+ * on the lane at point 'i + 1'. return the minimum number of side jumps the
+ * frog needs to reach any lane at point 'n' starting from lane 2 at point 0.
+ */
+
+int minSideJumps(int *obstacles, int obstaclesSize) {
+ int cnt = 0, status = 2;
+ for (int i = 0; i < obstaclesSize - 1; i++) {
+ if (obstacles[i + 1] == 2 && (status & (1 << 1))) {
+ status -= 2;
+ if (!status) {
+ cnt++;
+ status = 5;
+ if (obstacles[i])
+ status -= (1 << (obstacles[i] - 1));
+ }
+ } else if (obstacles[i + 1] == 3 && (status & (1 << 2))) {
+ status -= 4;
+ if (!status) {
+ cnt++;
+ status = 3;
+ if (obstacles[i])
+ status -= (1 << (obstacles[i] - 1));
+ }
+ } else if (obstacles[i + 1] == 1 && (status & 1)) {
+ status--;
+ if (!status) {
+ cnt++;
+ status = 6;
+ if (obstacles[i])
+ status -= (1 << (obstacles[i] - 1));
+ }
+ }
+ }
+ return cnt;
+}
+
+int main() {
+ int o1[] = {0, 1, 2, 3, 0}, o2[] = {0, 1, 1, 3, 3, 0},
+ o3[] = {0, 2, 1, 0, 3, 0};
+ printf("%d\n", minSideJumps(o1, ARRAY_SIZE(o1))); // expect: 2
+ printf("%d\n", minSideJumps(o2, ARRAY_SIZE(o2))); // expect: 0
+ printf("%d\n", minSideJumps(o3, ARRAY_SIZE(o3))); // expect: 2
+}