The code gives segmentation error, how? [closed]

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#include`<stdio.h>`
#include`<stdlib.h>`
int main()
{
    int k, i, j,tot=0, htot=0, vtot=0, dtot=0, m, n;        
    int 开发者_运维技巧a[8][8] = {
    {0,0,0,0,0,0,1,0},
    {0,0,0,1,0,0,0,0},
    {0,1,0,0,0,0,0,0},
    {1,0,0,0,0,0,0,0},
    {0,0,1,0,0,0,0,0},
    {0,0,0,0,0,1,0,0},
    {0,0,0,0,1,0,0,0},
    {0,0,0,0,0,0,0,1},
};

for(i=0;i<8;i++)        
{ 
    htot=0;
    printf("\n");
    for(j=0;j<8;j++)
    {
        htot += a[i][j];
        printf("%d\t", a[i][j]);    
    }    
    tot += htot ;
 }

if(tot == 8)
printf("Moving on to Vertical checking");
else
printf("Horizontal criterion not fulfilled %d ", tot);
tot=0;
for(j=0;j<8;j++)
{   
    vtot=0;
    printf("\n");
    for(i=0;i<8;i++)
    {
        vtot += a[i][j];
        printf("%d\t", a[i][j]);
    }
    tot +=vtot;
}   
if(tot == 8) 
printf("Moving on to Diagonal checking");
else
printf("Vertical criterion not fulfilled %d ", tot);    

for(i=0;i<8;i++)
{
    for(j=0;j<8;j++)
    {
    if(a[i][j])
    {
        m=i;
        n=j;
        while(n!=0)// running the loop leftwards
        {
        m++;
        n--;
        dtot +=a[m][n];     
        }
        printf("diagonal left total = %d", dtot);
        if(dtot == 1)
        {
        m=i;
        n=j;            
        while(n!=0)// running the loop rightwards
        {
        m++;
        n++;
        dtot +=a[m][n];
        }
        printf("diagonal right total = %d", dtot);
    }
} 
}
}
return 0;
}

---

while(n!=0)// running the loop rightwards
{
  m++;
  n++;
  dtot +=a[m][n];
}

That seems a pretty obvious crash to me. Increasing n and checking for n!=0.

The loop previous to this probably also crashes because m runs out of array index.

Put some printfs for m and n in those loops. Even better: think about the array index ranges before you write your code.

---

The diagonal runs aren't correctly bounded. You're only checking the n index, and you're checking it the wrong direction on the rightwards span. At some point n goes out of range and does an illegal array access.