CMSC 330 Homework #3– parameters Fall 20051. For each of the three parameter transition techniques call–by–value, call–by–reference, and call–by–name, give the output of the following program, written using C syntax.#include <stdio.h>int a, b, i;int c[4]= {100, 150, 175, 190};void f(int d, int e, int f) {d= 5;b= a + 3;e= 3;i= 0;f= 20;c[i]= 200;}int main() {a= 10;b= 5;i= 1;f(a, i, c[i]);printf("%d %d %d %d %d %d %d\n", a, b, i, c[0], c[1], c[2], c[3]);return 0;}2. Consider the following code written in OCaml syntax:let value = ref 1;;let f n = value := !value + n ; !value;;let g v w =let x = (f 2) inlet y = v + w inlet z = v * w inx + z - y;;g (f 1) (if !value > 4 then 6 else 5)(a) What output would the program pro duce if parameters were passed by value (as they actually arein OCaml)?(b) What output would the program produce if parameters were passed by need, as they are in Haskell?Recall that in call–by–need an actual parameter is evaluated only once, at the point where it isfirst used in the called procedure.(c) What output would the program produce if parameters were passed by name?13. What results would the following program, written in C syntax, produce if parameters were passed byneed? If C adopted call–by–need as its default parameter passing mechanism, what would the program’sresults be?#include <stdio.h>int func(int a, int b) {if (b == 0)return 0;else return func(a, b);}int main() {printf("%d\n", func(func(1, 1), func(0, 0)));return 0;}4. The following procedure will exchange the values of two integer variables if they are passed by reference.If the parameter transmission mechanism were changed to call–by–name, is there a set of input variableswhose values cannot be exchanged?void swap(x, y: integer);int temp;temp= x;x= y;y= temp}5. Give the least restrictive limits that can be placed on actual parameters so that call–by–name andcall–by–reference always give the same results in all
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