Replace line | File handling

Exercise 8. WAP to replace a specific line with another text in a file. 1

#include<stdio.h>
int main()
{
    FILE *fp, *fp2;
    int n=1, line;
    char str[80], text[80];
    fp=fopen("file.txt","r");
    fp2=fopen("temp.txt","w");
    printf("Enter line no. to replace: ");
    scanf("%d",&line);
    printf("Enter new text: ");
    fflush(stdin);
    gets(str);
    do{
        fgets(text,80,fp); //read line from file
        if(n==line) //skip the line to delete
        {
            fputs(str,fp2); //write new text in file
            fputs("\n",fp2); //write new text in file
        }
        else
            fputs(text,fp2); //write line in file
        n++;
    }while(!feof(fp));
    fclose(fp);
    fclose(fp2);
    remove("file.txt");
    rename("temp.txt","file.txt");
}

1st line
second line
3rd line

1st line
2nd line
3rd line