GATE Computer Science (CS) 2020 Solved Papers

            fun2(5)
$\downarrow$
Step - 1 0+fun1(5) = 0+5 = 5
$\downarrow \uparrow$
           returns(0+5)

            fun2(4)
$\downarrow$
Step - 2 5+fun1(4) = 5+(5+4) = 14
$\downarrow \uparrow$
           returns(5+4)

            fun2(3)
$\downarrow$
Step - 3 14+fun1(3) = 5+(5+4)+(5+4+3)=5+9+12 = 26
$\downarrow \uparrow$
           returns(12)

            fun2(2)
$\downarrow$
Step - 4 26+fun2(2) = 5+(5+4)+(5+4+3)+(5+4+3+2)=5+9+12+14 = 40
$\downarrow \uparrow$
           returns(14)

            fun2(1)
$\downarrow$
Step - 5 40+fun2(1) = 5+(5+4)+(5+4+3)+(5+4+3+2)+(5+4+3+2+1)=5+9+12 +14=55
$\downarrow \uparrow$
           returns(15)