直接在原矩阵上操作即可
int minPathSum(int** matrix, int matrixRowLen, int* matrixColLen ) {
for(int i=0;i<matrixRowLen;i++){
for(int j=0;j<*matrixColLen;j++){
if(i==0&&j!=0){
matrix[i][j]=matrix[i][j-1]+matrix[i][j];
}else if(j==0&&i!=0){
matrix[i][j]=matrix[i-1][j]+matrix[i][j];
}else if(i==0&&j==0){
matrix[i][j]=matrix[i][j];
}
else{
matrix[i][j]=(matrix[i][j-1]+matrix[i][j])>(matrix[i-1][j]+matrix[i][j])?matrix[i-1][j]+matrix[i][j]:matrix[i][j-1]+matrix[i][j];
}
}
}
return matrix[matrixRowLen-1][(*matrixColLen)-1];
}