LeetCode268缺失数字-C语言

 计算从0到第n个的元素之和，与数组之和的差值即为所缺元素

int missingNumber(int* nums, int numsSize) {
    int sum1 = 0;
    int sum2 = 0;
    for(int i = 0; i < numsSize; i++)
        sum1 += nums[i];
    sum2 = numsSize * (1 + numsSize)/2;
    return sum2 - sum1;
}