/*
 * Example of declaration, initialization, and reference of an array 
 */ 

#include <stdio.h> 

int
main()
{
    double x[8] = {16.0, 12.0, 6.0, 8.0, 2.5, 12.5, 14.0, -54.5};  
    double sum; 
    int i; 

    printf("array x = ");  
    for (i  = 0; i <= 7; ++i)
        printf("  %.1f",x[i]); 
    printf("\n"); 

    /* manipulate array x */ 

    printf("x[0] = %.1f\n", x[0]); 

    sum = x[0] + x[1]; 
    printf("sum = x[0]+x[1] .. %.1f\n", sum); 

    x[3] += 1.0; 
    printf("x[3] += 1.0 .. %.1f\n", x[3]); 

    x[2] = x[0] + x[1]; 
    printf("x[2] = x[0] +x[1] .. %.1f\n", x[2]); 

    printf("\n"); 
    
    /* manipulate array x with subscripts */ 
    i = 5; 
    printf("%.1f\n", x[i+1]); 
    printf("%.1f\n", x[i++]); 
    printf("%.1f\n", x[--i]); 
    printf("%.1f\n", x[(int)x[4]]); 

    // printf("x[2*i]= %.1f\n", x[2*i]);     // invalid 

    x[i-1]=x[i]; 
    x[i] = x[i+1]; 

    // x[i] - 1 = x[i];  invalid 

    return 0; 
}