????1??C??C++?????л??????????????У???????char???????Σ?short?? int?? long???? ???????float?? double??

???????????????λ?????????????????????????????????????????????????????ò??????????????????? unsigned?????????????????????????λ?????????λ????λ?0????????????λ?1??????????????????????????????????????????????????????±?????????Χ??

????2????????????????????????????????Χ??????????3?????Χ???????????μ????
????int main()
????{
????signed char ch = 127;
????ch += 1;
????printf("%d "?? ch);
????return 0;
????}
?????????????-128?????????ch????????127???????char?????????????????-128???????????????
???????????????127????????????????????01111111??
???????????01111111 + 00000001 = 10000000;
????????????????ch?????????????λ?1????????????????????????????????ò??????洢???????????????????????????????????????????????????????????????????????1????????????????
???????????????????????????裬?????????????????????????в????10000000??????10000000 - 00000001 = 01111111??????01111111????10000000??10000000 = 128??????????????????ch?-128.