#include<stdio.h>#include<string.h>#include<math.h>#define bool int int option[5];int order[5];float number[5];float curVal[4][5];//输出时用到的临时变量char outputStr[15];char outputStr2[15];char tempStr[15];char tempStr2[15];bool bfs(int k){ int m; if(k==3) { if(fabs(24.0-curVal[3][0])==0) return 1; else return 0; } else { int i,j; for(i=0;i<3-k;i++) { for(j=0;j<4;j++) { switch(j) { case 0: curVal[k+1][i]=curVal[k][i]+curVal[k][i+1]; break; case 1: curVal[k+1][i]=curVal[k][i]-curVal[k][i+1]; break; case 2: curVal[k+1][i]=curVal[k][i]*curVal[k][i+1]; break; case 3: curVal[k+1][i]=curVal[k][i]/curVal[k][i+1]; break; } for(m=0;m<i;m++) curVal[k+1][m]=curVal[k][m]; for(m=i+1;m<3-k;m++) curVal[k+1][m]=curVal[k][m+1]; option[k]=j; order[k]=i; if(bfs(k+1)) return 1; } } } return 0;}void OutPut(){ if(order[1]>=order[0]) order[1]++; order[2]=3-order[0]-order[1]; char op[4]={'+','-','*','/'}; sprintf(outputStr,"(%d%c%d)",(int)number[order[0]],op[ option[0] ],(int)number[order[0]+1]); strcpy(tempStr,outputStr); if(abs(order[0]-order[1])==2) { sprintf(outputStr2,"(%d%c%d)",(int)number[order[1]],op[ option[1] ],(int)number[order[1]+1]); strcpy(tempStr2,outputStr2); if(order[0]<order[1]) sprintf(outputStr,"%.*s%c%.*s",sizeof(tempStr),tempStr,op[ option[2] ],sizeof(tempStr2),tempStr2); else sprintf(outputStr,"%.*s%c%.*s",sizeof(tempStr2),tempStr2,op[ option[2] ],sizeof(tempStr),tempStr); } else { if(order[0]<order[1]) sprintf(outputStr,"(%.*s%c%d)",sizeof(tempStr),tempStr,op[ option[1] ],(int)number[order[1]+1]); else sprintf(outputStr,"(%d%c%.*s)",(int)number[order[1]],op[ option[1] ],sizeof(tempStr),tempStr); strcpy(tempStr,outputStr); if(order[2]==2) sprintf(outputStr,"%.*s%c%d",sizeof(tempStr),tempStr,op[ option[2] ],(int)number[order[2]+1]); else sprintf(outputStr,"%d%c%.*s",(int)number[order[2]],op[ option[2] ],sizeof(tempStr),tempStr); } printf("%sn",outputStr);}int main(){ int i; for(i=0;i<4;i++) { scanf("%f",&number[i]); curVal[0][i]=number[i]; } bfs(0); OutPut(); return 0;}
