题目
Given a non-negative integer represented as a non-empty array of digits, plus one to the integer.
You may assume the integer do not contain any leading zero, except the number 0 itself.
The digits are stored such that the most significant digit is at the head of the list.
分析
给出一个整数数组表示一个非负大整数。要求加一后返回。直接依次对各个位加一进行计算,当大于10进位。最后长度需要判断。
/**
* 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 *ans=(int *)malloc(sizeof(int)*(digitsSize+1));
*returnSize=0;
int temp=1;
for(int i=digitsSize-1;i>=0;i--)
{
temp=temp+digits[i];
if(temp>9)
{
ans[i+1]=temp%10;
temp=temp/10;
}
else
{
ans[i+1]=temp;
temp=0;
}
}
if(temp!=0)
{
ans[0]=1;
*returnSize=digitsSize+1;
}
else
{
for(int i=0;i<digitsSize;i++)
ans[i]=ans[i+1];
*returnSize=digitsSize;
}
return ans;
}