View Compilation Error

0_0_33797707_30598.cpp: In function 'void fft(CP*, int, int)':
0_0_33797707_30598.cpp:54:27: error: 'M_PI' was not declared in this scope
             CP w = rt(t * M_PI / m), u, v, z;
                           ^
0_0_33797707_30598.cpp:56:22: error: 'z' was not declared in this scope
                 for (z = (CP) {1, 0.0}, i = 0; i < k; ++i, z = z * w) {
                      ^
0_0_33797707_30598.cpp:57:21: error: 'u' was not declared in this scope
                     u = fg[i + j];
                     ^
0_0_33797707_30598.cpp:58:21: error: 'v' was not declared in this scope
                     v = z * fg[i + j + k];
                     ^