leetcode 066 Plus One（难易度：Easy）

Plus One

Given a non-negative number represented as an array of digits, plus one to the number.

The digits are stored such that the most significant digit is at the head of the list.

代码：

/**
* Return an array of size *returnSize.
* Note: The returned array must be malloced, assume caller calls free().
*/
int* plusOne(int* digits, int digitsSize, int* returnSize) {
int i;
int carry = 1;
int *new_digits = NULL;
for (i = digitsSize - 1; i >= 0; i--) {
int a = digits[i] + carry;
digits[i] = a % 10;
carry = a / 10;
if (carry == 0)
break;
}
if (carry == 1) {
digitsSize ++;
new_digits = (int*)malloc(digitsSize * sizeof(int));
new_digits[0] = 1;
for (i = digitsSize - 2; i >= 0; i--) {
new_digits[i + 1] = digits[i];
}
//digits = new_digits;
//free(digits);
*returnSize = digitsSize;
return new_digits;
}
else {
*returnSize = digitsSize;
return digits;
}
}

原题地址：https://leetcode.com/problems/plus-one/