src.cpp:4:21: error: size of array 'a' is too large
int a[100001][100001];
^
src.cpp: In function 'int main()':
src.cpp:15:10: error: 'a' was not declared in this scope
cin>>a[i][j];
^
src.cpp:19:8: error: 'a' was not declared in this scope
if(a[i][j]==x)dem++;
^