View Compilation Error

0_0_29100186_11992.cpp: In function 'void SPFA(int, int)':
0_0_29100186_11992.cpp:49:13: error: 'N_node' was not declared in this scope
    int mark[N_node] = {0};
             ^
0_0_29100186_11992.cpp:50:4: error: 'mark' was not declared in this scope
    mark[s] = 1;
    ^