View Compilation Error

0_0_30060864_14138.cpp: In function 'int main()':
0_0_30060864_14138.cpp:25:14: error: 'class std::vector<int>' has no member named 'push'
      vec[nk].push(i);
              ^
0_0_30060864_14138.cpp:47:14: error: 'class std::vector<int>' has no member named 'push'
       vec[i].push(j);
              ^