C语言-预估校正法求常微分方程

#include<stdio.h>
#include<math.h>
#define n 14
int main(){
    double a = 0.0, b = 1.4,h,m=0.0;
    //int n = 14;

    double x[n + ] = { 0.0 }, y[n + ] = {  };
    h = (b - a) / n;
    x[] = a;
    y[] = m;
    for (int i = ; i <= n; i++)
    {
        y[i] = y[i - ] + h*( + y[i - ] * y[i - ]);
        x[i] = a + i*h;
        y[i] = y[i - ] + h*0.5*(( + y[i - ] * y[i - ]) + (+y[i]*y[i]));
        printf("x[%d]=%e , y[%d]=%e\n",i, x[i], i, y[i]);
    }
    return ;
}