GATE CS question library

Assume the following C variable declaration: int *A[10], B[10][10]; Of the following expressions: $A[2]$ $A[2][3]$ $B[1]$ $B[2][3]$ which will not give compile-time errors if used as left hand sides of assignment statements in a C program?

Consider the following $C$ function. For large values of $y$, the return value of the function $f$ best approximates float f,(float x, int y) { float p, s; int i; for (s=1,p=1,i=1; i<y; i++) { p *= x/i; s += p; } return s; }

A processor uses $2-level$ page tables for virtual to physical address translation. Page tables for both levels are stored in the main memory. Virtual and physical addresses are both $32$ bits wide. The memory is byte addressable. For virtual to physical address translation, the $10$ most significant bits of the virtual address are used as index into …

Consider two languages $L_1$ and $L_2$ each on the alphabet $\Sigma$. Let $f : \Sigma^* \to \Sigma^*$ be a polynomial time computable bijection such that $(\forall x) [ x\in L_1$ iff $f(x) \in L_2]$. Further, let $f^{-1}$ be also polynomial time computable. Which of the following CANNOT be true?

Define languages $L_0$ and $L_1$ as follows : $L_0 = \{\langle M, w, 0 \rangle \mid M \text{ halts on }w\}$ $L_1 = \{\langle M, w, 1 \rangle \mid M \text{ does not halts on }w\}$ Here $\langle M, w, i \rangle$ is a triplet, whose first component $M$ is an encoding of a Turing Machine, second component $w$ is a string, and third component $i$ …

The cube root of a natural number $n$ is defined as the largest natural number $m$ such that $(m^3 \leq n)$ . The complexity of computing the cube root of $n$ ($n$ is represented by binary notation) is

If the strings of a language $L$ can be effectively enumerated in lexicographic (i.e., alphabetic) order, which of the following statements is true?