aboutsummaryrefslogtreecommitdiff
path: root/min_recolour_k_block.c
diff options
context:
space:
mode:
authorJack Sangdahl <[email protected]>2025-03-07 19:53:48 -0700
committerJack Sangdahl <[email protected]>2025-03-07 19:53:48 -0700
commit3148809e3af8febf1f684933da6f71f7af5fd2e6 (patch)
tree3d19cf63dd8faba1db8c046b19056ab6f0070538 /min_recolour_k_block.c
parent4802a9af9bbcf85f03605510ca7bd149128f5066 (diff)
downloadleetcode-3148809e3af8febf1f684933da6f71f7af5fd2e6.tar.gz
leetcode-3148809e3af8febf1f684933da6f71f7af5fd2e6.zip
2379. minimum recolours to get k consecutive black blocks
Diffstat (limited to 'min_recolour_k_block.c')
-rw-r--r--min_recolour_k_block.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/min_recolour_k_block.c b/min_recolour_k_block.c
new file mode 100644
index 0000000..253fad2
--- /dev/null
+++ b/min_recolour_k_block.c
@@ -0,0 +1,39 @@
+// 2379. Minimum Recolors to Get K Consecutive Black Blocks
+#include "leetcode.h"
+
+/*
+ * you are given a 0-indexed string 'blocks' of length 'n' where 'blocks[i]' is
+ * either 'W' or 'B', representing the colour of the i'th block. the characters
+ * 'W' and 'B' denote the colours white and black, respectively. you are also
+ * given an integer 'k', which is the desired number of consecutive black
+ * blocks. in one operation, you can recolour a white block such that it becomes
+ * a black block. return the minimum number of operations needed such that there
+ * is at least one occurence of 'k' consecutive black blocks.
+ */
+
+int minimumRecolors(char *blocks, int k) {
+ int n = strlen(blocks), min = INT_MAX, flips = 0, cnt = 0, i = 0;
+ for (int j = 0; j < n; ++j) {
+ if (blocks[j] == 'W') {
+ flips++;
+ cnt++;
+ } else if (blocks[j] == 'B')
+ cnt++;
+ if (cnt == k) {
+ min = fmin(min, flips);
+ if (blocks[i] == 'W') {
+ flips--;
+ cnt--;
+ } else
+ cnt--;
+ i++;
+ }
+ }
+ return min;
+}
+
+int main() {
+ char *b1 = "WBBWWBBWBW", *b2 = "WBWBBBW";
+ printf("%d\n", minimumRecolors(b1, 7)); // expect: 3
+ printf("%d\n", minimumRecolors(b2, 2)); // expect: 0
+}