ISO C ++禁止比较指针和整数：C错误中的文件处理

Question

I am trying to read from file. After reading, I want to display it's contents. My program looks like :

#include <stdio.h>
#include <string.h>
#include <stdio.h>


int main(int argc, char const *argv[])
{
    // 
    char array_of_input[10][10];
    FILE *fp;
    fp = fopen("input.txt","r+");
    int i = 0,j = 0;
    char ch;

    while ( !feof(fp))
    {
        ch = (char)fgetc(fp);
        printf("%c\n", ch );
        if ( ch == " ")
        {
            continue;
        }
        else if ( ch == "\n")
        {
            i++ ;
            j = 0 ;
        }
        else
        {
            array_of_input[i][j] = ch;
            j++;
        }
    }
    return 0;
}

But, I am getting error:

ISO C++ forbids comparison between pointer and integer [-fpermissive] if ( ch == " ")

fgetc(fp) returns int and then it's type-cast to char . I can't see any integer here.

Answer 1

ch is a char - you should compare it to a char literal (denoted by single quotes), not a string literal (denoted by double quotes):

if ( ch == ' ')
{
    continue;
}
else if ( ch == ' ')
{
    i++ ;
    j = 0 ;
}
else  // rest of code snipped