c++ - C language Function errors -

i use c language , need write program different function. have problems , didn't find solution.

i have 2 kind of function. one

int x(int i, int k){         int p, n;     return p + (i-1)*(n-1) + (k-1); } 

in function, have following error: error c2601: 'x' : local function definitions illegal

the other 1

void mode(){ matrix_entry temp; temp=m[i]; m[i]=m[small_i]; m[small_i]=temp; 

the problem matrix_entry, temp , m undeclared identifier

can me find mistakes? thanks

error c2601: 'x' : local function definitions illegal

it sounds you're defining function inside function; c++ doesn't allow that. move definition of x outside function it's in.

another possibility there's function before x, , missed out } @ end of function.

the problem matrix_entry, temp , m undeclared identifier in main have this:

firstly, types need declared before they're used. sounds function appears either before definition of matrix_entry, or in different source file.

either move definition of matrix_entry point before needs use it, or put in header , include each source file needs it. fix first 2 "undeclared identifier" errors matrix_entry , temp.

if m in main, it's not available in other functions. pass function(s) need it:

void mode(matrix_entry * m){     matrix_entry temp;     temp=m[i];     m[i]=m[small_i];     m[small_i]=temp; }  int main() {     matrix_entry *m = new matrix_entry  [10];      //...     mode(m);     //...      // don't forget delete new     // (better still don't new in first place,      // or use smart pointers if must)     delete [] m; }