[완료]우분투에서 컴파일 했는데 segmentation fault가 발생합니다;

#include <stdio.h>
#include <time.h>
#include <string.h>
 
int main(){
	FILE *a, *b, *c1, *c2, *c3;
	int aa[1000][1000]={0}, bb[1000][1000]={0}, br[1000][1000]={0};
	int cc1[1000][1000]={0}, cc2[1000][1000]={0},cc3[1000][1000]={0};
	int i=0, j=0, k;
	double ca1=0, ca2=0, ca3=0;
	double cts1, ctf1, cts2, ctf2, cts3, ctf3;
 
	a=fopen("array1.txt","r");
	b=fopen("array2.txt","r");
 
	while(!feof(a)){
		fscanf(a, "%d", &aa[i][j]);
		j++;
		if(j==1000){
			i++;
			j=0;
		}
		if(i==1000)
			break;
	}
 
	i=0;
	j=0;
 
	while(!feof(b)){
		fscanf(b, "%d", &bb[i][j]);
		j++;
		if(j==1000){
			i++;
			j=0;
		}
		if(i==1000)
			break;
	}
 
	cts1=clock();
	c1=fopen("array3_1.txt","a+");
	for(i=0;i<1000;i++){
		for(j=0;j<1000;j++){
			for(k=0;k<1000;k++) cc1[i][j]+=aa[i][k]*bb[k][j];
			fprintf(c1, "%d ", cc1[i][j]);
			ca1+=cc1[i][j];
			if(j==999)
				fprintf(c1, "\n");
		}
	}
	ctf1=clock();
	fprintf(c1,"\n average : %.2f\n", ca1/1000000);
	fprintf(c1,"time : %.2f", ctf1-cts1);
	fclose(c1);
 
	cts2=clock();
	c2=fopen("array3_2.txt","a+");
	for(i=0;i<500;i++){
		for(j=0;j<1000;j++){
			for(k=0;k<1000;k++) cc2[i][j]+=aa[i][k]*bb[k][j];
			fprintf(c2, "%d ", cc2[i][j]);
			ca2+=cc2[i][j];
			if(j==999)
				fprintf(c2, "\n");
		}
	}
	for(i=0;i<500;i++){
		for(j=0;j<1000;j++){
			for(k=0;k<1000;k++) cc2[i+500][j]+=aa[i+500][k]*bb[k+500][j];
			fprintf(c2, "%d ", cc2[i+500][j]);
			ca2+=cc2[i+500][j];
			if(j==999)
				fprintf(c2, "\n");
		}
	}
	ctf2=clock();
	fprintf(c2,"\n average : %.2f\n", ca2/1000000);
	fprintf(c2,"time : %.2f", ctf2-cts2);
	fclose(c2);
 
	for(i=0;i<1000;i++){
		for(j=0;j<1000;j++){
			br[i][j]=bb[j][i];
		}
	}
 
	cts3=clock();
	c3=fopen("array3_3.txt","a+");
	for(i=0;i<1000;i++){
		for(j=0;j<1000;j++){
			for(k=0;k<1000;k++) cc3[i][j]+=aa[i][k]*br[j][k];
			fprintf(c3, "%d ", cc3[i][j]);
			ca3+=cc3[i][j];
			if(j==999)
				fprintf(c3, "\n");
		}
	}
	ctf3=clock();
	fprintf(c3,"\n average : %.2f\n", ca3/1000000);
	fprintf(c3,"time : %.2f", ctf3-cts3);
	fclose(c3);
}