Problem 378

[Rafa3p]

I don't know why I'm getting WA.
For this test case I'm getting the same answer from uva.toolkit

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10
0 0 4 4 0 4 4 0
5 0 7 6 1 0 2 3
5 0 7 6 3 -6 4 -3
2 0 2 27 1 5 18 5
0 3 4 0 1 2 2 5
0 0 1 1 0 0 1 1
4 0 6 0 1 2 6 9
1 0 5 0 8 5 4 5
1 0 5 0 5 0 1 0
0 1 0 5 0 5 0 1

My code :

Code: Select all

#include <stdio.h>
int main(void)
{
    int n,x1,x2,y1,y2;
    double a1,a2,b1,b2,c1,c2,X,Y; /*Line Eq: ax+by+c=*/
    printf("INTERSECTING LINES OUTPUT\n");
    scanf("%d",&n);
    while(n--)
    {
        scanf(" %d %d %d %d ",&x1,&y1,&x2,&y2);
        if(x1^x2){ /*finding first line eq*/
            b1=1.0;
            a1 = (double) (y1-y2)/(x2-x1);
            c1 = (double) -(a1*x1+y1);
        }else{/*x1==x2 -> vertical line*/
            a1=1.0; b1=0.0; c1 = -x1;
        }

        scanf(" %d %d %d %d ",&x1,&y1,&x2,&y2);
        if(x1^x2){ /*finding second line eq*/
            b2=1.0;
            a2 = (double) (y1-y2)/(x2-x1);
            c2 = (double) -(a2*x2+y2);
        }else{/*x1==x2 -> vertical line*/
            a2=1.0; b2=0.0; c2 = -x1;
        }

        if((a1==a2) &&(b1==b2)){ /*True ->parallel*/
            if(c1==c2)printf("LINE\n"); /*Same line*/
            else printf("NONE\n");
        }
        else{ /*Finding the intersection points*/
            X = (b2*c1 - c2*b1)/(a2*b1-b2*a1);
            if(b1==0)/*Avoiding division for 0*/
                Y = (a2*X+c2)/b2;
            else
                Y = (a1*X+c1)/b1;
            if(Y==0)printf("POINT %.2f 0.00\n",X);
            else if(X==0) printf("POINT 0.00 %.2f\n",-Y);
            else printf("POINT %.2f %.2f\n",X,-Y);
        }
    }
    printf("END OF OUTPUT");

    return 0;
}


Please give me some help.

[Rafa3p]

I changed this:

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            if(Y==0)printf("POINT %.2f 0.00\n",X);
            else if(X==0) printf("POINT 0.00 %.2f\n",-Y);
            else printf("POINT %.2f %.2f\n",X,-Y)


for this:

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            if(X==0)printf("POINT 0.00");
            else printf("POINT %.2f",X);
            if(Y==0) printf(" 0.00\n");
            else printf(" %.2f\n",-Y);


And got AC.
I did this because sometimes i was printing "-0.00" instead of "0.00"