Why the output print 70 instead of 106? Can you explain

Question

#include <stdio.h>
int main() {
int var=0101;
var=var+5;
printf("%d",var);
return 0;
}

Answer 1

0 is an octal literal, so 0101 would be 8^0 + 8^2 = 65 in decimal.
Then you add 5 so thats 70.