c - 不确定我是否应该调用强制转换或对参数执行某些操作

Question

#include <stdio.h>
int main()
{ 
    double dMinimum;
    double dMaximum;
    char szName[] = "Armvad Ezikon";
    double dScoreM[] =  { 40, 0, 30, 55, 0, 25 };
    int iScoreCount = 6; 
    determineMinMax(dScoreM, iScoreCount , &dMinimum, &dMaximum);
    printf("For %s, minimum = %lf and maximum = %lf ", szName, dMinimum, dMaximum);
    return 0;
}
void determineMinMax( double  dScoreM[] ,  int  iScoreCount ,  double *pdMin, double *pdMax) 
{
    int i;
    *pdMin = 200.0;  // arbitrary high value
    *pdMax = 0.0;
    for(i = 0; i < iScoreCount; i++)
    {
        if(dScoreM[i] < *pdMin)
            *pdMin = dScoreM[i];
        if(dScoreM[i] > *pdMax)
            *pdMax = dScoreM[i];
    }
}

当我尝试编译时出现此错误，是因为我没有正确转换吗？

exampleone.c:13:6:警告:“defineMinMax”的类型冲突[默认启用]

void确定MinMax( double dScoreM[] , int iScoreCount , double *pdMin, ^exampleone.c:9:1:注意:之前的“defineMinMax”隐式声明位于此处 确定MinMax(dScoreM, iScoreCount , &dMinimum, &dMaximum);

Answer 1

使用前必须先声明:

void determineMinMax( double  dScoreM[] ,  int  iScoreCount ,  double *pdMin, double *pdMax);
int main(void){
  ..
}

或者简单地说，

void determineMinMax( double  dScoreM[] ,  int  iScoreCount ,  double *pdMin, double *pdMax){

 ...

}

int main(void){
  ...
}

否则它会与编译器假定的隐式声明int certainMinMax()相冲突。但在C99、C11中这是一个错误。