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authorJack Sangdahl <[email protected]>2025-08-17 08:23:37 -0600
committerJack Sangdahl <[email protected]>2025-08-17 08:23:37 -0600
commit5d449e06b0ccf99ad3d10e2ed2c37e6e902bab1c (patch)
tree9b7652508cd2aef2ffd2fe16afaf2acdc41eeedd /new_21_game.c
parentf359b85a14d62e61cd108f8c1f5818f08cde5a20 (diff)
downloadleetcode-5d449e06b0ccf99ad3d10e2ed2c37e6e902bab1c.tar.gz
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837. new 21 game
Diffstat (limited to 'new_21_game.c')
-rw-r--r--new_21_game.c19
1 files changed, 9 insertions, 10 deletions
diff --git a/new_21_game.c b/new_21_game.c
index 4076f33..a9a0f5a 100644
--- a/new_21_game.c
+++ b/new_21_game.c
@@ -1,37 +1,36 @@
// 837. New 21 Game
-#include <stdio.h>
-#include <stdlib.h>
+#include "leetcode.h"
/*
* alice plays the following game, loosely based on the card game "21". alice
* starts with 0 points and draws numbers while she has less than 'k' points.
* during each draw, she gains an integer number of points randomly from range
- * '[1, max_pts]', where 'max_pts' is an integer. each draw is independent and
+ * '[1, maxPts]', where 'maxPts' is an integer. each draw is independent and
* the outcomes have equal posibilities. alice stops drawing numbers when she
* gets 'k' or more points. return the probability that alice has 'n' or fewer
* points. answers within 10^-5 of the actual answer are considered accepted
*/
-double new21Game(int n, int k, int max_pts) {
- if (!k || n >= k + max_pts)
+double new21Game(int n, int k, int maxPts) {
+ if (!k || n >= k + maxPts)
return 1.0;
- double *dp = malloc((n + 1) * sizeof(double));
+ double *dp = (double *)malloc((n + 1) * sizeof(double));
dp[0] = 1.0;
double sum = 1.0, ans = 0.0;
for (int i = 1; i <= n; ++i) {
- dp[i] = sum / max_pts;
+ dp[i] = sum / maxPts;
if (i < k)
sum += dp[i];
else
ans += dp[i];
- if (i - max_pts >= 0)
- sum -= dp[i - max_pts];
+ if (i - maxPts >= 0)
+ sum -= dp[i - maxPts];
}
+ free(dp);
return ans;
}
int main() {
- // new21Game(21,17,10);
printf("%f\n", new21Game(10, 1, 10)); // expect: 1.00000
printf("%f\n", new21Game(6, 1, 10)); // expect: 0.60000
printf("%f\n", new21Game(21, 17, 10)); // expect: 0.73278