ju.cpp

#include <stdio.h>
#include <complex.h>
#include <math.h>


#ifndef complex
#define complex _Complex
#endif

int main() {
    complex double z;
    complex double c;

    c = 1+2i;
    z = 1.+2.i;

    int i = 0, n = 100;
    while( cabs(z) > 0.01 || i < n) {
        z = z*z + c;
        i++;
    }

    printf( "%d %g %gi", i, creal(z), cimag(z));
}