1、七種qsort排序方法V本文中排序都是采用的從小到大排序一、對int類型數(shù)組排序intnum100;Sample:intcmp(constvoid*a,constvoid*b)return*(int*)a-*(int*)b;qsort(num,100,sizeof(num0),cmp);二、對char類型數(shù)組排序(同int類型)charword100;Sample:intcmp(constvoid*a,constvoid*b)return*(char*)a-*(char*)b;qsort(word,100,sizeof(word0),cmp)三、對double類型數(shù)組排序(特別要注意)doub

2、lein100;intcmp(constvoid*a,constvoid*b)return*(double*)a>*(double*)b?1:-1;qsort(in,100,sizeof(in0),cmp)；四、對結(jié)構(gòu)體一級排序structIndoubledata;intother;s100按照data的值從小到大將結(jié)構(gòu)體排序，關(guān)于結(jié)構(gòu)體內(nèi)的排序關(guān)鍵數(shù)據(jù)data的類型可以很多種,參考上面的例子寫intcmp(constvoid*a,constvoid*b)return(*(In*)a).data>(*(In*)b).data?1:-1;qsort(s,100,sizeof(s0),

3、cmp);五、對結(jié)構(gòu)體二級排序structInintx;inty;s100;按照x從小到大排序，當(dāng)x相等時按照y從大到小排序intcmp(constvoid*a,constvoid*b)structIn*c=(In*)a;structIn*d=(In*)b;if(c->x!=d->x)returnc->x-d->x;elsereturnd->y-c->y;qsort(s,100,sizeof(s0),cmp);六、對字符串進行排序structInintdata;charstr100;s100;/按照結(jié)構(gòu)體中字符串str的字典順序排序intcmp(constv

4、oid*a,constvoid*b)returnstrcmp(*(In*)a)->str,(*(In*)b)->str);qsort(s,100,sizeof(s0),cmp);七、計算幾何中求凸包的cmpintcmp(constvoid*a,constvoid*b)重點cmp函數(shù)，把除了1點外的所有點，旋轉(zhuǎn)角度排序structpoint*c=(point*)a;structpoint*d=(point*)b;if(calc(*c,*d,p1)<0)return1;elseif(!calc(*c,*d,p1)&&dis(c->x,c->y,p1.x,p1.y)<dis(d-