ISO c++禁止在devc++中比较指针和整数[-fpermissive]错误

ISO c++禁止在devc++中比较指针和整数[-fpermissive]错误这基本上是一个点和框的游戏错误是在检查函数中大约有六个地方，我比较了[I -1][j]=="_"帮我解决这个问题

#include <stdio.h>
#include<conio.h>
#include<string.h>
#include<stdlib.h>
int p=0;
int g=1;int p1s=0;int p2s=0;
char pl,pt1,pt2;
char p1[20];
char p2[20];
char a[17][35];
void printer(){int i,j;
system("cls");
printf("score ---->  %s => %d      %s => %dn",p1,p1s,p2,p2s); 
printf(" 00  01  02  03  04  05  06  07  08  09  10  11  12  13  14  15  16  17 n");
    for(i=0;i<17;i++){if(i%2==0)printf("%c ",'a'+(i/2));for(j=0;j<35;j++)printf("%c ",a[i][j]);printf("n");}
}
void check(char c,char d,int i1,int i2,int p){int i,j,k,l;
    if(c==d){
    i=c-'a';i=2*i;j=2*i1+1;
    if(a[i-2][j]=="_" && a[i-1][j-1]=="|" && a[i-1][j+1]== "|"){if(p%2==0){p1s++;a[i-1][j]=pt1;};if(p%2==1){p2s++;a[i-1][j]=pt2;}}
    if(a[i+2][j]=="_"&&a[i+1][j-1]=="|"&&a[i+1][j+1]=="|"){if(p%2==0){p1s++;a[i+1][j]=pt1;};if(p%2==1){p2s++;a[i+1][j]=pt2;}}
    }
}
void game(){    int i,j,k,i1,i2,i3;
    for(i=0;i<17;i++){for(j=0;j<35;j++){if(i%2==0){if(j%2==0)a[i][j]='.';else a[i][j]=' ';}else a[i][j]=' ';}}
    printer();
    char c[4];char d[4];
    while(g==1){ if(p%2==0){printf("%s's turn",p1)}
    if(p%2==1){printf("%s's turn",p2)}
    printf("enter first coordinaten");
    gets(c);
    printf("enter second coordinaten");
    gets(d);
    i1=10*(c[1]-'0')+(c[2]-'0');
    i2=10*(d[1]-'0')+(d[2]-'0');
    if(c[2]=='')i1=c[1]-'0';  /* correction if single digit is entered */
    if(d[2]=='')i2=d[1]-'0';
    i3=d[0]-c[0]+i2-i1;
    i3=d[0]-c[0]+i2-i1;
    if(i3!=1){printf("invalid moven");continue;}
    if(!((c[0]-'a')<25)&&!((d[0]-'a')<25)){printf("invalid moven");continue;}
    if(!(i1<18)&&!(i2<18)){printf("invalid moven");continue;}
    if(c[0]==d[0]){j=c[0]-'a';j=2*j;k=i2*2+1;if(a[j][k]=='_'){printf("repeated linen");continue;}else a[j][k]='_';}
    if(i2==i1){j=c[0]-'a';j=2*j+1;k=i1*2+1;if( a[j][k]=='|'){printf("repeated linen");continue;}else a[j][k]='|';}
    check(c[0],d[0],i1,i2,p);
    printer();
    }
}
int main (){
    printf("Enter first player's name:n");
    gets(p1);
    printf("Enter second player's name:n");
    gets(p2);
    pt1=p1[0];
    pt2=p2[0];
    if(p1[0]==p2[0])pt2=p2[1];
    game();
    return 0;
    getch();
}

我用devcpp编程A是二维弦为什么这种比较是无效的?