C语言输出整数时如何控制位宽

?C???,????printf???????????????????:

1. ??????????????,?????????????%Nd,??N????????,d?????????,?????????6??????,????"m"?

int num = 123;
printf("m\n", num); // ????? "   123"

2. ?????????????????????,?????????????%Nd,??N????????,????????,?????????,?????????6??????,????????,????"%-6d"?

int num = 123;
printf("%-6d\n", num); // ????? "123   "

3. ????????????????0???,?????????????%0Nd,??N????????,????????,??0?????,?????????6??????,????0??,????"d"?

int num = 123;
printf("d\n", num); // ????? "000123"

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