Here are some solved Infosys placement paper questions.

1)void main()
{
int i;
for(i=1;i<4,i++)
switch(i)
case 1: printf("%d",i);break;
{
case 2:printf("%d",i);break;
case 3:printf("%d",i);break;
}
switch(i) case 4:printf("%d",i);
}

a)output is 1,2,3,4
b)run-time error.
c)Compile time error
d)none.

Answer :output is 1,2,3,4

2) void main()
{
char *s="\12345s\n";
printf("%d",sizeof(s));
}

a)2
b)3
c)6
d)error.

Answer is 6

3)void main()
{
unsigned i=1; /* unsigned char k= -1 => k=255; */
signed j=-1; /* char k= -1 => k=65535 */
/* unsigned or signed int k= -1 =>k=65535 */
if(i<j)
printf("less");
else
if(i>j)
printf("greater");
else
if(i==j)
printf("equal");
}

a)less
b)greater
c)equal
d)none

Answer is less

4) void main()
{
float j;
j=1000*1000;
printf("%f",j);
}

a) 1000000
b) Overflow
c) Error
d) None

Answer is None