func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m, a[3010][6010], fa[18010000];   int dx[9] = {-1, -1, -1, 0, 0, 1, 1, 1}, dy[9] = {-1, 0, 1, -1, 1, -1, 0, 1};   inline int read() {     int x = 0, f = 0;     char ch = getchar();     while (!isdigit(ch)) f = ch ==  - , ch = getchar();     while (isdigit(ch)) x = (x << 3) + (x << 1) + ch - 48, ch = getchar();     return f ? -x : x;   }   inline int find(int x) { return fa[x] == x ? x : fa[x] = find(fa[x]); }   inline int calc(int x, int y) { return (x - 1) * m * 2 + y; }   int main() {     int ans = 0;     n = read(), m = read();     int Q = read();     for (int i = 1; i <= n; i++)       for (int j = 1; j <= 2 * m; j++) fa[calc(i, j)] = calc(i, j);     if (m == 1) {       puts( 0 );       return 0;     }     while (Q--) {       int x = read(), y = read();       int flag = 0;       for (int i = 0; i < 8; i++) {         int xx = x + dx[i], yy = y + dy[i];         if (yy == 0) yy = 2 * m;         if (xx < 1 || xx > n || !a[xx][yy]) continue;         for (int j = 0; j < 8; j++) {           int xxx = x + dx[j], yyy = y + m + dy[j];           if (yyy > 2 * m) yyy = 1;           if (xxx < 1 || xxx > n || !a[xxx][yyy]) continue;           if (find(calc(xx, yy)) == find(calc(xxx, yyy))) {             flag = 1;             break;           }         }       }       if (flag) continue;       a[x][y] = a[x][y + m] = 1;       ans++;       int fx1 = find(calc(x, y)), fx2 = find(calc(x, y + m));       for (int i = 0; i < 8; i++) {         int xx = x + dx[i], yy = y + dy[i];         if (yy > m) {           if (a[xx][yy]) fa[find(calc(xx, yy))] = fx1;           if (a[xx][1]) fa[find(calc(xx, 1))] = fx2;         } else if (yy < 1) {           if (a[xx][yy + m]) fa[find(calc(xx, yy + m))] = fx2;           if (a[xx][2 * m]) fa[find(calc(xx, 2 * m))] = fx1;         } else {           if (a[xx][yy]) fa[find(calc(xx, yy))] = fx1;           if (a[xx][yy + m]) fa[find(calc(xx, yy + m))] = fx2;         }       }     }     printf( %d n , ans);     return 0;   }   