Merge branch 'master' of https://github.com/begeekmyfriend/leetcode

Author: begeekmyfriend

160_intersection_of_two_linked_list/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test intersection.c

160_intersection_of_two_linked_list/intersection.c

@@ -0,0 +1,53 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+struct ListNode {
+    int val;
+    struct ListNode *next;
+};
+
+static struct ListNode *getIntersectionNode(struct ListNode *headA, struct ListNode *headB)
+{
+    struct ListNode *p;
+    for (p = headA; p->next != NULL; p = p->next) {}
+    p->next = headB;
+
+    bool first = true;
+    struct ListNode *p0, *p1;
+    for (p0 = headA, p1 = headA; p1 != NULL && p1->next != NULL; p0 = p0->next, p1 = p1->next->next) {
+        if (p0 == p1 && !first) {
+            p0 = headA;
+            while (p0 != p1) {
+                p0 = p0->next;
+                p1 = p1->next;
+            }
+            p->next = NULL;
+            return p0;
+        }
+        first = false;
+    }
+
+    p->next = NULL;
+    return NULL;
+}
+
+int main(int argc, char **argv)
+{
+    struct ListNode *headA = malloc(sizeof(*headA));
+    struct ListNode *headB = malloc(sizeof(*headB));
+    struct ListNode *common = malloc(sizeof(*common));
+
+    headA->val = 1;
+    headB->val = 2;
+    common->val = 4;
+    headA->next = common;
+    headB->next = common;
+    common->next = NULL;
+
+    struct ListNode *p = getIntersectionNode(headA, headB);
+    if (p != NULL) {
+        printf("%d\n", p->val);
+    }
+    return 0;
+}

167_two_sum_ii/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test two_sum.c

167_two_sum_ii/two_sum.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+/**
+ * Return an array of size *returnSize.
+ * Note: The returned array must be malloced, assume caller calls free().
+ */
+static int* twoSum(int* numbers, int numbersSize, int target, int* returnSize)
+{
+    int i = 0, j = numbersSize - 1;
+    while (i < j) {
+        int diff = target - numbers[i];
+        if (diff < numbers[j]) {
+            while (i < --j && numbers[j + 1] == numbers[j]) {}
+        } else if (diff > numbers[j]) {
+            while (++i < j && numbers[i - 1] == numbers[i]) {}
+        } else {
+            *returnSize = 2;
+            int *indexes = malloc(*returnSize * sizeof(int));
+            indexes[0] = i + 1;
+            indexes[1] = j + 1;
+            return indexes;
+        }
+    }
+
+    *returnSize = 0;
+    return NULL;
+}
+
+int main(int argc, char **argv)
+{
+    if (argc < 3) {
+        fprintf(stderr, "Usage: ./test target n1 n2...");
+        exit(-1);
+    }
+
+    int i, count = argc - 2;
+    int target = atoi(argv[1]);
+    int *nums = malloc(count * sizeof(int));
+    for (i = 0; i < count; i++) {
+        nums[i] = atoi(argv[i + 2]);
+    }
+
+    int number = 0;
+    int *indexes = twoSum(nums, count, target, &number);
+    if (indexes != NULL) {
+        printf("%d %d\n", indexes[0], indexes[1]);
+    }
+    return 0;
+}

168_excel_sheet_column_title/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test sheet_column.c

168_excel_sheet_column_title/sheet_column.c

@@ -0,0 +1,36 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+static char *convertToTitle(int n)
+{
+    if (n <= 0) {
+        return "";
+    }
+
+    char *result = malloc(1024);
+    int len = 0;
+    do {
+        result[len++] = ((n - 1) % 26) + 'A';
+        n = (n - 1) / 26;
+    } while (n > 0);
+    result[len] = '\0';
+
+    int i, j;
+    for (i = 0, j = len - 1; i < j; i++, j--) {
+        char c = result[i];
+        result[i] = result[j];
+        result[j] = c;
+    }
+    return result;
+}
+
+int main(int argc, char **argv)
+{
+    if (argc != 2) {
+        fprintf(stderr, "Usage: ./test n\n");
+        exit(-1);
+    }
+
+    printf("%s\n", convertToTitle(atoi(argv[1])));
+    return 0;
+}

169_majority_element/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test majority.c

169_majority_element/majority.c

@@ -0,0 +1,37 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+static int majorityElement(int* nums, int numsSize)
+{
+    int i, count = 1;
+    int major = nums[0];
+    for (i = 1; i < numsSize; i++) {
+        if (count == 0) {
+            major = nums[i];
+            count++;
+        } else if (major == nums[i]) {
+            count++;
+        } else {
+            count--;
+        }
+    }
+
+    return major;
+}
+
+int main(int argc, char **argv)
+{
+    if (argc < 2) {
+        fprintf(stderr, "Usage: ./test target n1 n2...\n");
+        exit(-1);
+    }
+
+    int i, count = argc - 1;
+    int *nums = malloc(count * sizeof(int));
+    for (i = 0; i < count; i++) {
+        nums[i] = atoi(argv[i + 1]);
+    }
+
+    printf("%d\n", majorityElement(nums, count));
+    return 0;
+}

171_excel_sheet_column_number/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test sheet_column.c

171_excel_sheet_column_number/sheet_column.c

@@ -0,0 +1,24 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+static int titleToNumber(char *s)
+{
+    int n = 0;
+    while (*s != '\0') {
+        n *= 26;
+        n += *s++ - 'A' + 1;
+    }
+
+    return n;
+}
+
+int main(int argc, char **argv)
+{
+    if (argc != 2) {
+        fprintf(stderr, "Usage: ./test ABC\n");
+        exit(-1);
+    }
+
+    printf("%d\n", titleToNumber(argv[1]));
+    return 0;
+}