将下列PDL语言：PROCEDUREaverage; *最多输人N个值（以一999为输人结束标志），计算位于给定范围内的那些值 （称为有效输人值）的平均值，以及输人值的个数和有效值的个数* INTERFACE RETURNS average,total.input,total.valid; INTERFACE ACCEPTS n,value,minimum,maximum; TYPE value[1,n]IS SCALAR ARRAY; TYPE average,total.input,total.valid,minimum,maximum,sum IS SCALAR,; TYPE n,iIS INTEGER; i=1; total.input=total.valid=0； sum=0； DO WHILE value[i]<>-999 and total.input<n increment total.input by 1; IF value[i]>=minimum AND value[i]<=maximum THEN increment total.valid by 1; sum=sum+value[ i] ELSE skip ENDIF increment iby 1; ENDDO IFtotal.valid>0 THEN average-sum/total.valid; ELSE average--999； ENDIF END average 转换成C语言

以下是将PDL语言转换成C语言的代码：

#include <stdio.h>

void average(int n, int value[], int minimum, int maximum, float *average, int *total_input, int *total_valid) {
    int i = 0;
    float sum = 0;
    *total_input = 0;
    *total_valid = 0;

    while (value[i] != -999 && *total_input < n) {
        (*total_input)++;
        if (value[i] >= minimum && value[i] <= maximum) {
            (*total_valid)++;
            sum += value[i];
        }
        i++;
    }

    if (*total_valid > 0) {
        *average = sum / *total_valid;
    } else {
        *average = -999;
    }
}

int main() {
    int n = 10;
    int value[] = {2, 5, 7, 8, 10, -999};
    int minimum = 3;
    int maximum = 8;
    float avg;
    int total_input;
    int total_valid;

    average(n, value, minimum, maximum, &avg, &total_input, &total_valid);

    printf("Average: %.2f\n", avg);
    printf("Total Input: %d\n", total_input);
    printf("Total Valid: %d\n", total_valid);

    return 0;
}

注意，C语言中没有PDL语言中的INTERFACE和TYPE关键字，需要用其他方式来实现函数参数和类型定义。此外，PDL语言中的increment和-=操作符在C语言中没有直接对应的形式，需要通过+=和-=来实现。