测试主函数设计如下: include <stdio. h> main (void) {inta=11,3,4,517,18,31,33} int x=17. int bn: bn BSearch(a, x, 0,7: if(bn==-1) printf("x不在数组a中"); else printi("x在数组a的下标%d中",bn)9 测试主函数设计如下： # include <stdio.h> main(void) { int a[] = {1, 3, 4, 5, 17, 18, 31, 33}; int x = 17; int bn; bn = BSearch(a, x, 0,7); if(bn == -1) printf("x不在数组a中"); else printf("x在数组a的下标%d中", bn); }