在此代码中第35行的abs()函数出错 . 我选择的编译器:c(4.3.2)
在底部看错误 .
void bfs(pair<int,int> pixelpos){
bfsq.push(pixelpos);
int u,v,i,j;
pair<int,int> tmpq;
while(!bfsq.empty()){
tmpq = bfsq.front();
u = tmpq.first; v = tmpq.second;
bfsq.pop();
r(i,u-square_dist,u+square_dist) r(j,v-square_dist,v+square_dist)
if(inrange(i,j)){
// ERROR HERE DOWN IN abs() fn
int dist = abs(pixelpos.first - i) + abs(pixelpos.second -j); // Line: 35
if(graph[i][j]>dist){
graph[i][j] = dist;
bfsq.push(pair<int,int> (i,j));
}
}
}
prog.cpp:在函数'void bfs(std :: pair)'中:
prog.cpp:35: error: call of overloaded 'abs(int)' is ambiguous
/ usr / include / c /4.3/cmath:99:注意:候选人是:double std :: abs(double)/ usr / include / c /4.3/cmath:103:注意:float std :: abs(float)
/ usr / include / c /4.3/cmath:107:注意:long double std :: abs(long double)
prog.cpp:35: error: call of overloaded 'abs(int)' is ambiguous
/ usr / include / c /4.3/cmath:99:注意:候选人是:double std :: abs(double)
/ usr / include / c /4.3/cmath:103:注意:float std :: abs(float)
/ usr / include / c /4.3/cmath:107:注意:long double std :: abs(long double)
What might be the reason?
1 回答
出错的原因可能是您没有包含 Headers
<cstdlib>
.标准C功能
在C头
<stdlib.h>
中声明 .虽然C标准允许在全局命名空间中放置标准C名称,但最好使用限定名称作为示例