View Compilation Error

0_0_31494956_29876.cpp: In function 'void dijkstra(int)':
0_0_31494956_29876.cpp:24:15: error: 'vis' cannot be used as a function
    while(vis(n)==0)
               ^
0_0_31494956_29876.cpp: At global scope:
0_0_31494956_29876.cpp:47:1: error: expected declaration before '}' token
 }
 ^