Merge pull request neetcode-gh#2323 from seinlin/523

Create 0523-continuous-subarray-sum.c

c/0523-continuous-subarray-sum.c

@@ -0,0 +1,47 @@
+#define FREE_AND_RETURN(x, y) \
+free(x); \
+return y;
+
+bool checkSubarraySum(int* nums, int numsSize, int k){
+    unsigned int* sums = NULL;
+    int i, j;
+
+    // Early return edge cases.
+    if (numsSize < 2) {
+        return false;
+    }
+    if (k == 1) {
+        return true;
+    }
+
+    sums = (unsigned int*)malloc(numsSize * sizeof(unsigned int));
+    sums[0] = nums[0];
+    for (i = 1; i < numsSize; i++) {
+        // Return true, when there are two continuous nums are times of k.
+        if (nums[i] % k == 0 && nums[i - 1] % k == 0) {
+            FREE_AND_RETURN(sums, true);
+        }
+
+        sums[i] = nums[i] + sums[i - 1];
+
+        // Return true, when the current subarray sum is times of k.
+        if (sums[i] % k == 0) {
+            FREE_AND_RETURN(sums, true);
+        }
+    }
+
+    for (i = 0; i < numsSize; i++) {
+        if (sums[i] < k) {
+            continue;
+        }
+
+        for (j = 0; j < i - 1; j++) {
+            // Return true, when the any subarray sum is times of k.
+            if ((sums[i] - sums[j]) % k == 0) {
+                FREE_AND_RETURN(sums, true);
+            }
+        }
+    }
+
+    FREE_AND_RETURN(sums, false);
+}