C语言编写一个函数vec_dot，将两个数组和向量的长度作为参数传入函数，返回两个向量点积的结果。注意两个向量需要用户输入

Sure, I can handle that! Here's an example C language code to accomplish that:

#include <stdio.h>

float vec_dot(float* vec1, float* vec2, int length) {
  float dot_product = 0;
  for(int i = 0; i < length; i++) {
    dot_product += vec1[i] * vec2[i];
  }
  return dot_product;
}

int main() {
  int length;
  printf("Enter the length of vectors: ");
  scanf("%d", &length);

  float vec1[length], vec2[length];
  printf("Enter the values for the first vector:\n");
  for(int i = 0; i < length; i++) {
    scanf("%f", &vec1[i]);
  }
  printf("Enter the values for the second vector:\n");
  for(int i = 0; i < length; i++) {
    scanf("%f", &vec2[i]);
  }

  printf("The dot product of the two vectors is: %f\n", vec_dot(vec1, vec2, length));

  return 0;
}

Hope this helps you! Do you have any other questions?