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Signed-off-by: begeekmyfriend <[email protected]>

Author: begeekmyfriend

050_pow/pow.c

@@ -1,3 +1,4 @@
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -11,6 +12,10 @@ static double fast_pow(double x, int n)
 
 static double my_pow(double x, int n)
 {
+    if (n == INT_MIN) {
+        double t = 1 / fast_pow(x, -(n / 2));
+        return t * t;
+    }
     return n < 0 ? 1 / fast_pow(x, -n) : fast_pow(x, n);
 }
 

070_climbing_stairs/climb_stairs.c

@@ -21,11 +21,21 @@ static int dfs(int n, int *count)
 
 static int climbStairs(int n)
 {
+#if 0
     int *count = malloc((n + 1) * sizeof(int));
     memset(count, 0, (n + 1) * sizeof(int));
     count[1] = 1;
     count[2] = 2;
     return dfs(n, count);
+#else
+    int i, a = 1, b = 2, c;
+    for (i = 3; i <= n; i++) {
+        c = a + b;
+        a = b;
+        b = c;
+    }
+    return n == 1 ? a : (n == 2 ? b : c);
+#endif
 }
 
 int main(int argc, char **argv)