c语言 13-1、13-2

13 - 1、

#include <stdio.h>

int main(void)
{
    FILE *fp;
    char filename[FILENAME_MAX];
    printf("filename: "); scanf("%s", filename);
    
    if((fp = fopen(filename, "r")) == NULL)
        printf("aFile does not exist.
");
    else
    {
        printf("File exists.
");
        fclose(fp); 
    }
    return 0;
}

13 - 2、

#include <stdio.h>

int main(void)
{
    FILE *fp;
    char filename[FILENAME_MAX];
    printf("filename: "); scanf("%s", filename);
    
    if((fp = fopen(filename, "r")) == NULL)
        printf("aFile does not exist.
");
    else
    {
        fp = fopen(filename, "w");
        printf("File cleared successfully.
");
        fclose(fp);
    }
    return 0;
}