[英]Segmentation fault error for a matrix assignment
這是我的代碼,用於創建類似於游戲“地雷”的網格:
#include <stdio.h>
#include <stdlib.h>
int main(){
int nr, nc, ** mtx, i, j;
//Matrix costruction
FILE * inStr;
inStr = fopen("brasa.dat","r");
if(inStr == NULL){
printf("\nProblem while opening the file.\n");
return 1;
}
fscanf(inStr, "%d%d", &nr, &nc);
mtx = (int**) malloc(nr * sizeof(int*));
if(mtx == NULL){
printf("\nMemory allocation error.\n");
return 1;
}
else{
for(i = 0; i < nr; i++)
mtx[i] = (int*) malloc(nc * sizeof(int));
if(mtx[i] == NULL){
printf("\nMemory allocation error.\n");
return 1;
}
}
//Filling matrix
for(i = 0; i < nr; i++){
for(j = 0; j < nc; j++)
mtx[i][j] = 0;
}
while(!feof(inStr)){
fscanf(inStr,"%d %d",&i,&j);
mtx[i][j] = 9;
}
fclose(inStr);
for(i = 0; i < nr; i++){
for(j = 0; j < nc; j++){
if(i == 0){
if(j == 0){
if(mtx[i][j+1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j+1] > 8)
mtx[i][j]++;
}
else if(j == nc-1){
if(mtx[i][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j] > 8)
mtx[i][j]++;
}
else{
if(mtx[i][j-1] > 8)
mtx[i][j]++;
else if(mtx[i][j+1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j+1] > 8)
mtx[i][j]++;
}
}
else if(i == nr-1){
if(j == 0){
if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j+1] > 8)
mtx[i][j]++;
else if(mtx[i][j+1] > 8)
mtx[i][j]++;
}
else if(j == nc-1){
if(mtx[i][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j] > 8)
mtx[i][j]++;
}
else{
if(mtx[i][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j+1] > 8)
mtx[i][j]++;
else if(mtx[i][j+1] > 8)
mtx[i][j]++;
}
}
else if(j == 0){
if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j+1] > 8)
mtx[i][j]++;
else if(mtx[i][j+1] > 8)
mtx[i][j]++;
else if(mtx[i-1][j+1] > 8)
mtx[i][j]++;
else if(mtx[i-1][j] > 8)
mtx[i][j]++;
}
else if(j == nc-1){
if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i][j-1] > 8)
mtx[i][j]++;
else if(mtx[i-1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i-1][j] > 8)
mtx[i][j]++;
}
else{
if(mtx[i-1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j-1] > 8)
mtx[i][j]++;
else if(mtx[i+1][j] > 8)
mtx[i][j]++;
else if(mtx[i+1][j+1] > 8)
mtx[i][j]++;
else if(mtx[i][j+1] > 8)
mtx[i][j]++;
else if(mtx[i-1][j+1] > 8)
mtx[i][j]++;
else if(mtx[i-1][j] > 8)
mtx[i][j]++;
}
if(mtx[i][j] > 8)
printf("*\t");
else
printf("%d\t", mtx[i][j]);
}
}
free(mtx);
return 0;
}
在程序執行期間出現分段錯誤。 經過幾次測試,我發現問題應該在85行和158行之間。您能幫我嗎?
您的訪問權限無效
// ...
else if(i == nr-1){ // i is nr - 1
if(j == 0){
// ...
}
else if(j == nc-1){
// ...
else if(mtx[i+1][j] > 8) // i + 1 is nr (invalid access)
// ...
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.