boxes.cpp: In function 'long long int delivery(int, int, int, int*)':
boxes.cpp:17:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = k-1; i < l.size(); i += k) {
~~^~~~~~~~~~
boxes.cpp:20:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = k-1; i < r.size(); i += k) {
~~^~~~~~~~~~
boxes.cpp:23:17: warning: conversion to 'int' from 'std::vector<long long int>::size_type {aka long unsigned int}' may alter its value [-Wconversion]
lsz = l.size();
~~~~~~^~
boxes.cpp:24:17: warning: conversion to 'int' from 'std::vector<long long int>::size_type {aka long unsigned int}' may alter its value [-Wconversion]
rsz = r.size();
~~~~~~^~